The Analysis of the Application of Student-centered Teaching Model in English Teaching of Middle Sch
我国高校本科生转专业现状与对策研...

我国高校本科生转专业现状与对策研究——以浙江师范大学为例摘要lIIIIIIIIIIIIIIIIIIIIIY18049452002年9月,复旦大学244名学生重新选择专业转到新系,这样人数众多的转系转专业,首开了我国高校大规模制度化的转专业之“门”,至今很多相关论述都以此作为中国高校转专业工作开始的标志。
在转专业的本科生中,或因高考发挥欠佳被调剂录取,或因填报志愿盲目跟风,或因奉父母之命未能对自己准确定位,这些学生进入高校之后yJ…发现对所选专业不能很好适应,继而萌生“转”意。
然而转专业政策的实施并不是高校的目的,而是服务于一个崇高的办学理念——让每个学生都有机会按照自身特点,自由选择适合的高等教育;让每个学生都能充分发展个性潜质,在得其所长的同时成爿…报国。
一句话,最好的高校应该是一片肥沃的土壤,让洒下的种子自由发展,而不是丌出一模一样的花。
本文是对我国高校本科生转专业现状与对策的研究,选取了数所高校近几年实施的转专业政策进行比较分析,并以浙江师范大学转专业政策及三年转专业状况作为个案进行研究,基本框架如下:绪论部分简要介绍本研究的背景、意义、内容和方法,着重对国内外现有研究内容进行梳理,并对相关概念进行界定。
第二部分着重分析我国高校本科生转专业政策的实施背景,从转专业政策实施的现实条件入手,进而调查数所综合类和师范类高校的转专业政策,具体从给予学生转专业的次数、转专业的时间安排、对申请转专业学生的资格限制、规定的转专业学生名额比例等方面比较其异同,分析政策规定中存在的问题。
第三部分为了更详细地了解转专业现状,特选取浙江师范大学2009年的转专业政策——《浙江师范大学关于做好2009年全F1制本科生转专业工作的通知》作为个案进行研究,以2007年至2009年连续三年的已转专业本科生数据作为研究对象,统计分析转专业的人数变化、专业的流动特点;继而选择数名学院老师及本科生进行访谈,分析转专业实际工作中存在的问题;同时从我国高校本科生转专业的宏观原因——自由发展,保证兴趣;追求功利,着眼就业;转换环境,解决困难等三方面,对参与2009年转专业工作的部分本科尘进行问卷调查,分析促使本科生产生转专业意向的微观原因,例如对所选专业的满意程度、所学专业在志愿中的位置、家庭成员的文化程度等。
最新小学英语全英说课稿(精选10篇)

小学英语全英说课稿(精选10篇)小学英语全英说课稿(精选10篇)小学英语全英说课稿(一):The lesson I am going to talk about is fom the teaching mateialBook One ,Unit 8。
the thid pat that is used by the kids in Gade One 。
一、Analysis of the teaching mateial (说教材)This is a dialogue that happens in the fuit shop 。
seveal sentences suound selling and buying the fuit ple instuctions and act accodingly ,and they can say simple bes fom one to ten 。
The main language points in this unit is to make sentences using the fuit and numbes feely and municate s of the nouns 。
Accoding to the kids English level and the coesponding content in the daily life ,I give them some exta extending 。
To tain thei ability of municate s (教学目标)1。
knos :(知识技能目标)eviees of the ten diffeent kinds of fuit and ecognize the numbes fom one to ten 。
Undestand simple instuctions about the numbes and act accodingly。
The Analysis of Scaffolding Instruction Application in Senior High School English Writing

zwwx@ 2019 年 09 月
Tel:+86-551-65690811 65690812
The Analysis of Scaffolding Instruction Application in Senior High School English Writing Teaching — Based on Students of Zuoyun Higቤተ መጻሕፍቲ ባይዱ School in Datong
LEI Ye-hua
(Bohai University, Jinzhou 121000, China)
Abstract: This study aims to investigate the relationship between English Writing achievement and scaffolding instruction with 100 Students from Zuoyun high school as subjects in a quantitative method. Results show that: 1) On the whole, high school students have good use of scaffolding in English writing. 2) The application of scaffolding instruction in high school English writing teaching has a significant positive correlation with English writing performance. 3) On the whole, there is a significant difference in the appli⁃ cation of the scaffolds in English writing between high and low-score group students. Key words:the application of scaffolding instruction; English writing scores; students in Grade One of high school 中图分类号:H319 文献标识码:A 文章编号:1009-5039(2019)18-0270-02
Analysis of the students

Analysis of the studentsThe students of Grade2 have got certain listening ability, which still needs well improving. And their speaking ability is not as good as expected, which will be improved in this period through some exercise.Analysis of the book1) Status and function ofthe teaching materialThis period will arouse the students’ interest in creating something useful. With the interest they will learn to express and support an opinion.2) Teaching aimsKnowledge goalLead the students to imagine things they would like to invent and express their thoughts on such new inventions.Moral goalLead the students to get an idea of the qualities an inventor must have, such as imagination, bravery, perseverance.。
2 Analysis of the learners•T he students in my class are of different levels so I should adapt the lesson to each of them and try to solve different kinds of problems which may appear in the lesson.There are 63 students in my class, which is large .•S o I often use some activities in the class to finish some tasks such as individual, pair or group work to let each of them have more chances to practise English and involve actively in the lesson, thus to make some improvement .•T ask-based teaching mode;•A ctivity-based teaching :class work;•individual work ; group work说学生1.我校属于省一级重点中学,虽然喜欢英语并且有信心学好英语的学生占了半数以上(57%),但由于英语水平参差不齐,学习压力大,学习策略与方法不合理,还是有33%的学生不喜欢英语。
近四十年国内学业负担研究的知识图谱分析

Advances in Education 教育进展, 2023, 13(9), 6479-6487 Published Online September 2023 in Hans. https:///journal/ae https:///10.12677/ae.2023.1391009近四十年国内学业负担研究的知识图谱分析王晨晨苏州大学教育学院,江苏 苏州收稿日期:2023年8月2日;录用日期:2023年8月30日;发布日期:2023年9月6日摘要过重的学业负担不仅危害着中小学生的身心健康,也危害着素质教育的顺利实施,严重影响我国基础教育事业的发展。
要寻求解决过重学业负担问题的途径,首当其冲的是对国内学业负担研究的现状形成整体性认识。
本文借助Citespace 知识图谱软件,对近四十年来CNKI 数据库中收录的学业负担相关研究文献进行分析。
研究结果表明,我国学业负担研究与国家相关政策的出台紧密相关;学业负担研究领域呈现出以高校尤其是师范类大学为主体,各省市教育科学研究院也不甘落后的论文出版格局;其热点在于界定学业负担的概念与本质,注重多种研究方法的运用,关注减负与发展素质教育之间的联系。
关键词学业负担,国内,知识图谱Research on Domestic Academic Burden in Recent 40 Years: An Analysis Based on CiteSpace MapsChenchen WangSchool of Education, Soochow University, Suzhou JiangsuReceived: Aug. 2nd , 2023; accepted: Aug. 30th , 2023; published: Sep. 6th , 2023AbstractExcessive academic burden not only endangers the health of primary and secondary school stu-dents, but also endangers the implementation of quality education and seriously affects the de-velopment of basic education. In order to find a way to solve the problem of excessive academic burden, the first thing is to form an overall understanding of the current situation of domestic王晨晨academic burden research. With the help of CiteSpace maps, this paper analyzes the academic burden related research literature collected in CNKI database in the past 40 years. The results show that the study of academic burden is closely related to the implementation of national re-lated policies; the research field of academic burden presents a paper publishing pattern with universities, especially normal universities, as the main body, and provincial institutes of educa-tion science are not willing to lag behind. Its focus is to define the concept and essence of academic burden, pay attention to the application of a variety of research methods, and pay attention to the relationship between reducing the burden and developing quality education.KeywordsAcademic Burden, Domestic, Mapping Knowledge Domains Array Copyright © 2023 by author(s) and Hans Publishers Inc.This work is licensed under the Creative Commons Attribution International License (CC BY 4.0)./licenses/by/4.0/1. 引言随着1955年教育部正式出台减负政策——《关于减轻中、小学学生过重负担的指示》,有关如何减轻学业负担的讨论一直在持续。
Education Research.

BLACK-BOX TESTING IN THE INTRODUCTORYPROGRAMMING CLASSTamara BabaianComputer Information Systems DepartmentBentley Collegetbabaian@Wendy LucasComputer Information Systems DepartmentBentley CollegeABSTRACTIntroductory programming courses are often a challenge to both the students taking them and the instructors teaching them. The scope and complexity of topics required for learning how to program can distract from the importance of learning how to test. Even the textbooks on introductory programming rarely address the topic of testing. Yet, anyone who will be involved in the system development process should understand the critical need for testing and know how to design test cases that identify bugs and verify the correct functionality of applications. This paper describes a testing exercise that has been integrated into an introductory programming course as part of an overall effort to focus attention on effective software testing techniques.1 A comparison of the performance on a common programming assignment of students who had participated in the testing exercise to that of students who had not demonstrates the value of following such an approach.Keywords: testing, debugging, black-box method, introductory programming1 A shorter version of this paper, entitled Developing Testing Skills in an Introductory Programming Class, was presented at the 2005 International Conference on Informatics Education Research.I. INTRODUCTIONFor several years now, object-oriented languages have predominated within introductory programming courses in the Computer Science and Information Systems curricula. Programming in general does not come naturally to all students, and object-oriented concepts can be especially daunting. Students struggling to write their first programs quickly succumb to the mantra that it compiles and runs - therefore it is correct. The importance of testing is lost on these novices in their rush to submit functioning code. Integrated Development Environments (IDEs), which are invaluable in many ways, may have the unintended consequence of supporting this attitude; a simple click of a button compiles and runs code with astonishing speed (particularly to those of us who remember punch cards). It is so easy to recompile that one can fall into the trap of making changes and rerunning the program without analyzing errors and thinking through the code to address them. While syntactical errors are caught and promptly drawn to the programmer’s attention by the IDE, trapping logical errors requires careful design of test cases and thorough analysis of outputs. The necessity for these skills is often lost on the novice. A far greater risk is that the novice will become a developer who never learned the value of thorough testing. Attesting to the validity of this concern is the estimated $59.5 billion that software bugs are costing the U.S. each year [Tassey, 2002]; early detection of these errors could greatly reduce these costs [Baziuk, 1995]. As noted by Shepard et al. [2001], although testing typically takes at least 50% of the resources for software development projects, the level of resources devoted to testing in the software curriculum is very low. This is largely due to a perceived lack of available time within a semester for covering all of the required topics, let alone making room for one that may not be viewed as core to the curriculum. The motivation for the work presented here arises from the need for teaching solid testing skills right from the start. Students must learn that testing should be givenat least as much priority as providing the required functionality if they are to become developers of high-quality software.This paper describes a testing exercise that has been used successfully within an introductory programming course taught using the Java language at Bentley College. This course is part of the curriculum within the Computer Information Systems (CIS) Department, and is required for CIS majors but open to all interested students. The contents of this course are in keeping with the IS2002 Model Curriculum [Gorgone et al., 2002], which recommends the teaching of object-oriented programming and recognizes the need for testing as a required part of the coursework. While faculty readily acknowledge this need, developing a similar appreciation for testing in our students has proven far more difficult. The testing exercise described here has been found to be an effective step in this process.The next section of this paper reviews research that is relevant to the work presented here. We then provide an overview of the course and a detailed description of the testing exercise. In order to assess the impact of this exercise, we present an analysis of student performance on a related coding assignment. This paper concludes with a discussion of directions for future work.II. LITERATURE REVIEWThe low priority given to testing within the software curriculum and the need for that to change has been acknowledged in the literature. Shepard, Lamb, and Kelly [2001], who strongly argue for more focus on testing, note that Verification and Validation (V&V) techniques are hardly taught, even within software engineering curriculum. They propose having several courses on testing, software quality, and other issues associated with V&V available for undergraduates. Christensen [2003] agrees that testing should not be treated as an isolated topic, but rather should be integrated throughout the curriculum as“core knowledge.” The goal must be on producing reliable software, and he proposes that systematic testing is a good way to achieve this.Much of the relevant literature describes the use of Extreme Programming (XP) [Beck, 2000] techniques in programming courses for teaching testing. XP advocates a test-first approach in which unit tests are created prior to writing the code. For students, benefits of this approach include developing a better understanding of the project’s requirements and learning how to test one module or component at a time.XP plays a key role in the teaching guidelines proposed by Christensen [2003], which include: (1) fixing the requirements of software engineering exercises on high quality, (2) making quality measurable by teaching systematic testing and having students follow the test-driven approach of XP, and (3) formulating exercises as a progression, so that each builds on the solution to the prior exercise. These guidelines have been applied by Christensen in an advanced programming class.Allen, Cartwright, and Reis [2003] describe an approach for teaching production programming based on the XP methodology. The authors note that, “It is impossible to overstate the importance of comprehensive, rigorous unit testing since it provides the safeguard that allows students to modify the code without breaking it” [Allen et al., 2003, p. 91]. To familiarize students with the test-first programming approach, they are given a simple, standalone practice assignment at the beginning of the course for which most of their grade is based on the quality of the unit tests they write. Another warm-up assignment involves writing units tests for a program written by the course’s instructors. These exercises were found to be effective in teaching students how to write suitable tests for subsequent assignments.The approaches to teaching testing described above are very similar to the approach described in this paper. What differentiates our testing exercise andfollow-up coding assignment is that they are intended for beginning programmers, not the more experienced ones who would be found in advanced or production-level programming courses. This presents the challenge of teaching students who are only beginning to grasp the concept of programming about the importance of testing and the complexities associated with developing effective test cases.Edwards [2004] does address the issues of teaching testing in an introductory CS course and recommends a shift from trial-and-error testing techniques to reflection in action [Schön, 1983], which is based on hypothesis-forming and experimental validation. He advocates the Test Driven Development (TDD) method [Edwards, 2003], which requires, from the very first assignment, that students also submit test cases they have composed for verifying the correctness of their code. Their performance is assessed on the basis of “how well they have demonstrated the correctness of their program through testing” [Edwards, 2004, p. 27]. Edwards [2004] focuses on tools that support students in writing and testing code, including JUnit (/), DrJava [Allen et al., 2002], and BlueJ [Kölling, 2005], and on an automated testing prototype tool called Web-CAT (Web-based Center for Automated Testing) for providing feedback to students. Patterson, Kölling, and Rosenberg [2003] also describe an approach to teaching unit testing to beginning students that relies on the integration of JUnit into BlueJ. While Snyder [2004] describes an example that introduces testing to beginning programmers, his work is built around the use of an automated system for conditional compilation.What differentiates these works from our own is our explicit focus on the testing exercise itself, rather than on the different types of tools that provide assistance with testing, as a means for supporting the teaching of testing to novices. Our testing assignment requires a thorough analysis by students of the inner workings of a program for which they do not have access to the code. Theassignment’s components must therefore be carefully designed for use by beginning programmers.III. COURSE BACKGROUNDIn this section we present an overview of the Programming Fundamentals course and describe how instruction in software testing is positioned within its curriculum. This is the first programming course within the CIS Major at Bentley College, and it is taught using the Java programming language. While it is required for majors, it also attracts non-majors, with students also differing in terms of backgrounds in programming and class levels. To accommodate the majority of students enrolled in this course and prepare them for subsequent classes in software development, it is targeted towards those students who do not have any prior programming experience. The goal of this course is for students to develop basic programming and problem-solving skills. This is accomplished through lectures, in-class laboratory sessions for writing and testing code, and assignments that are completed outside of the classroom.Approximately two-thirds of the material covered in this course focuses on basic data types, control structures, and arrays. The remainder of the semester is spent introducing object-oriented programming concepts, including classes and objects, and instance versus static variables and methods. All of these concepts are reinforced through frequent programming assignments, with an assignment due every one to two weeks. Students are expected to complete all assignments on their own, without collaborating with others in the class, in accordance with our academic honesty policy. There are no group assignments in this course, as we feel that, at the introductory level, individual effort is required to absorb abstract programming concepts. Laboratory assistants and instructors are always on-hand to answer any questions with assignments and help direct student efforts without revealing solutions.Concepts related to the system lifecycle are sprinkled throughout the course to keep the students aware of the big picture and to help explain and motivate effective development practices associated with object-oriented languages. Strongly emphasized are testing and debugging techniques, the development of sound programming logic, and the writing of well-structured code. The decision to devote class time specifically to teaching program verification as part of this course arose from a curriculum revision process. Several of the faculty who teach development courses acknowledged that insufficient training in testing methodologies during the introductory programming classes was adversely impacting the students’ attitudes toward program verification in later courses. By addressing testing early and often in the sequence of courses within our major, we could help students develop proper testing techniques while stressing the important role of program validation within the system development process.As part of this effort, during the introductory lectures we stress the fact that the longest and most expensive part of the software lifecycle is spent in maintenance. We point out that maintenance expenses depend on the clarity of the code and its documentation, as well as on the robustness of the testing performed during the software development process. The formal introduction to testing and verification of software is given in the third week of the course, after most of the basic programming concepts have been covered and students are capable of composing a program with more than one possible outcome. Such an early introduction is necessary to facilitate the early application of testing techniques by students. This also serves to reinforce the importance of testing and good testing practices, which students will apply throughout the rest of the semester in their programming assignments. In addition, opportunities to develop test cases arise during completion of in-class programming exercises. These present students with the opportunity to learn from both the instructor and each other about the process of developing and implementing test cases.IV. TESTING EXERCISEIn this section, we provide a detailed description of the testing exercise that has been included in the Programming Fundamentals course. To set the stage for the testing exercise, the black-box (specification-based) method of testing was introduced in a lecture given during the third week of the course. This lecture was then followed by the testing assignment, in which the students were asked to perform black-box testing of a completed program. They were provided with a requirements specification for the program and with a compiled Java application, created by the instructor, which implemented those requirements with varying degrees of completeness and correctness. As part of their task, students would need to identify the ways in which the program failed to meet the specification. In the following sections, we describe the set of requirements for the program, the compiled code to be tested, the student deliverables and evaluation guidelines, and the instructor’s evaluation process.PROBLEM REQUIREMENTS SPECIFICATIONThe application described in the requirements specification for the testing assignment is for automating the billing process for an Internet café (see Figure 1). The specified billing rules resemble those that are typically found in contemporary commerce applications and are based on multiple dimensions, including: the time when the service was provided, the length of that service, the charges associated with the service, and whether or not the customer holds a membership in the Café-Club.In selecting the application domain for this assignment, we wanted one that would reinforce the importance of testing. An Internet café is something with which students are familiar, most likely in the capacity of a customer who would want to be sure that the café was correctly billing for its services. Students could also conceivably be owners of such an enterprise, who would be equally if notmore concerned with the correctness of the billing process. This domain should therefore contribute to the students’ motivation to verify the billing functionality.A new Internet café operates between the hours of 8 a.m. and 11 p.m. The regular billing rate for Internet usage from its computers is 25 cents per minute. In addition, the following rules apply:1. Regular (non-member) customers are always billed at the regular rate.2. Café-Club members only receive a special discount during the discount period between 8a.m. and 2 p.m.: the first two hours within that period are billed at the rate of 10 cents perminute; all time past the first two hours (but within the discount period) is billed at the rate of 20 cents per minute. Any time outside of the discount period is billed at the regular rate. 3. If the total cost exceeds $50, it is discounted by 10%.Note that rule 2 above applies to Café-Club members only and rule 3 applies to all customers. The program should help automate customer billing for the Internet café. The program should work exactly as follows.The user should be prompted to enter:1. The letter-code designating the type of the customer: 'r' or 'R' for a regular customer, 'm'or 'M' for a club member.2. The starting hour.3. The starting minute.4. The ending hour.5. The ending minute of the customer's Internet session.The starting and ending hours are to be entered based on a 24 hour clock. Your program must then output the cost in dollars of the service accordin g to the above billing rules.Figure 1. Billing Program RequirementsIt was also important to provide an application that was understandable without being trivial. The logic of the billing rules is straightforward; at the same time, there is a rich variety of situations requiring different computational processes. Several categories of test cases as well as a number of different boundary conditions are necessitated and require thorough testing to verify the correctness of the application.PROGRAM TO BE TESTEDEvery student was e-mailed a compiled Java application implementing the billing program requirements presented in Figure 1. In order to maximize independent discovery and minimize the potential for students to discuss andcopy each other’s solutions, two different billing programs were implemented. Students were informed that more than one program was being distributed, but since the names of both programs and their compiled file sizes were identical and they did not have access to the source code, they could not readily tell who else had been sent the same version.Both versions contained four logical errors that were deliberately and carefully entered into the code by the instructor. While the errors in each version were different, the scope of the input data with which students would need to test in order to identify the incorrect operations was consistent. Hence, the likelihood of finding the problems with the implementations was comparable for the two versions.ASSIGNMENT DELIVERABLES AND EVALUATION GUIDELINES There are two parts to the deliverable that students were required to submit for this assignment (see Appendix I for the complete description). The purpose of the first part is to document the set of test cases they designed and the outcomes of each of the individual tests they ran using those test cases. Test case descriptions must include a complete specification of program inputs, the correct output value (i.e., given those inputs, the cost in dollars of the service based on the business rules shown in Figure 1), and the actual output value produced by the program. The objective of the test must also be described. For example, an objective might be to: “Test regular customer outside of the discount period.” The aim of this requirement is to help the students organize their testing process and learn to identify and experiment with distinct categories of input data.Students were encouraged to design test cases for different computational scenarios and boundary conditions. While there were no explicit requirements on the number of test cases, students were told that they should only include cases with valid application data (e.g. hour values between 0 and 23, inclusive). Thiswas done to limit the scope of the problem to a manageable size for beginning programmers.The second part of the assignment is to summarize the errors identified during testing in the form of hypotheses regarding the unmet requirements of the program. An example of a hypothesis might be: “The 10% discount is not applied within the discount period.” In order for a student to form such a hypothesis, which precisely identifies the error and the circumstances in which it occurs, observations from multiple test cases must be combined. For this particular example, one must combine the results of testing for the correct application of the 10% discount rule during different periods of service for each of the customer types. Thus, students must use their analytical skills to generalize the results of individual tests to a higher level of abstraction. In order to direct the students in this analytical process, the assignment explicitly suggests that they form additional test cases to verify or refine their initial hypotheses.INSTRUCTOR’S EVALUATION OF THE ASSIGNMENTIn evaluating the first part of this assignment, student submissions were checked against a list of twenty-five categories of test cases derived by the instructor. For the assignment’s second part, the summary of findings was checked for consistency with each student’s test case results. Appendix II shows the point value assigned to each graded component of the assignment, with a maximum possible score of 10 points. The first 5.5 points were awarded based on the degree of coverage of the students’ test sets with respect to the instructor’s categorizations. The next 2 points were for the number of actual problems with the code that were correctly identified (Diagnosed problems/summary of findings). The final 2.5 points were for the completeness of the descriptions provided for each test case (Presentation). This last component refers to the format rather than the content of the tests. For example, using the interaction shown in Appendix I, the student should show the starting hour of 12and the starting minute of 0 as two separate values rather than as one value of 12:00.The majority of students precisely identified two of the four program errors. Approximately 68% of submissions received scores of 8 and above out of a possible 10, 20% scored between 6 and 8, and 12% scored below 6. The value of this assignment cannot, however, be discerned solely on the basis of the students’ performance on it; rather, it is how it influences performance on future programming assignments that is most important, as discussed next.V. ASSESSING THE IMPACT OF TRAINING IN TESTINGIn this section, we present an assessment of the results of using the previously described approach to teaching students how to test by evaluating the performance of two groups of students on a common programming assignment. Students in Group 1 were enrolled in this course in a prior semester and did not receive any class time or homework training in testing methodology. They also did not complete the testing exercise. Group 2 students were enrolled in this course in the following semester; they were given a lecture on the black-box method and completed the testing exercise (but had not yet received the instructor’s evaluations of that exercise) prior to being given the programming assignment described below. These differences in testing preparation were the only distinguishing variation between the two groups; there were no significant differences between the number of students in each group or their composition in terms of their majors and prior exposure to programming. All the students were beginning programmers enrolled for the first time in a programming course at Bentley College, and most were in either their sophomore or junior year. Attendance by students in both groups was typically 85% or more for all class sessions.The assignment given to the students was to create a program for the billing requirements specification presented in Figure 1. Both groups were given the programming assignment at approximately the same point in the course. The students’ submissions were tested against the same suite of sixteen test cases. Table 1 summarizes the results of the comparison between the two groups of students on the common programming assignment.Table 1. Students’ Performance on the Billing Requirements ProgramGroup 1: Without testing assignmentGroup 2: With testing assignmentTotal number of students enrolled 39 40Total number of submissions 25 35Percentage of students who submitted 64% 87%Median number of failed tests 5 5Percentage of submitted programs with0 errors detected8% 20% The above comparison yields interesting results. The submission rate, i.e.,the percentage of enrolled students who submitted a program that compiled and ran, is far higher for the Group 2 students, who had received instruction in testing and completed the testing exercise. Based on a two-tailed t-test comparison, the means of the number of submissions are significantly different, with p = 0.015 using the standard 0.05 significance level. This suggests that problem analysis inthe form of creating test cases brings students closer to an understanding of the algorithm being tested. Based on this increased level of understanding, studentsin Group 2 had the confidence to complete an assignment that was perceived by many in Group 1 as being too difficult.The median number of failed test cases is the same for both groups and, while the percentage of “error-free” submissions (those that passed all 16 tests)is 2.5 times higher for Group 2, the means are not significantly different (usingthe two-tailed t-test, p = 0.206). A likely explanation is that only the “best” students in Group 1 were able to complete the programming assignment, so theirperformance was similar to that of those in Group 2, in which a far greater percentage of students were able to complete the assignment.Throughout the semester, it was also observed by the instructor that the explicit lecture on testing coupled with the testing exercise had served to increase the Group 2 students’ awareness of the variety of usage scenarios that could be derived from a program specification. Students were more likely to consider different input categories and suggest test cases capturing important boundary conditions based on the specification. The instructor felt that the introduction of black-box testing to the curriculum had an overall positive impact on the students’ ability to produce robust applications.VI. DISCUSSIONWhile introducing the concept of testing and having students create test cases are not uncommon activities throughout Computer Science and Information Systems curricula, the approach described here has several unique characteristics and advantages. First of all, the testing exercise requires that students develop a set of test cases for an instructor-created, compiled program, rather than for code they wrote themselves. This approach clearly separates the testing of the code from its development and is, therefore, a purer way for students to experience black-box testing than the TDD methodology [Edwards 2003] described earlier. Since creating the set of test cases prior to working on the implementation is not enforced by the TDD method, the testing performed by students may be biased by their knowledge of the code’s structure and how they chose to implement the program. Students participating in our testing exercise did not have access to the source code and were, thus, solely dependent on the requirements specification for developing their test cases.Providing students with a program that has been carefully crafted to include observable errors enables a second unique aspect to the assignment:。
沉积盆地流体包裹体研究的理论与实践_欧光习

矿物岩石地球化学通报#油气流体及成岩作用#Bu lletin of M ineralogy,Petrology and Geoch emistryVol.25No.1,Jan.2006收稿日期:2005-10-31收到,12-30改回基金项目:国家重点基础研究发展规划资助项目(2003CB214605);中石化西部新区勘探指挥部重点资助项目第一作者简介:欧光习(1968-),男,研究员,专业方向:有机岩石学与流体地球化学.E -m ail:ougu angxi@263.n et.沉积盆地流体包裹体研究的理论与实践欧光习1,李林强1,孙玉梅21.核工业北京地质研究院,北京100029;2.中海石油研究中心,河北高碑店074010摘 要:流体包裹体作为地质流体研究的重要手段,在沉积盆地油气成藏条件分析和有机/无机矿产共存、共生关系研究中起着不可替代的作用。
本文以鄂尔多斯北部、塔里木东北部、辽西-冀北坳陷中-新元古界等地的油气藏、砂岩型铀矿为例,通过流体包裹体岩相学、偏光-荧光特征、显微测温、显微傅里叶红外和包裹体同位素定年技术,结合盆地构造、地层埋藏史、热演化史等资料,探讨了流体包裹体在定性、定量分析有机/无机矿产的成矿流体性质、来源、期次、流体运/聚时空及油气成藏演化等方面的应用。
关 键 词:流体包裹体岩相学;显微成分分析;包裹体定年;方法与实践;沉积盆地中图分类号:P 593 文献标识码:A 文章编号:1007-2802(2006)01-0001-11Theory and Application of the Fluid Inclusion Research on the Sedimentary BasinsOU Guang -xi 1,LI Lin -qiang 1,Sun Yu -mei 21.Beijing Research Institute of Uranium Geolog y,Beij ing 100029,China;OOC ResearchCenter,Gaobeid ian,H ebei 074010,ChinaAbstract:As an important means of geofluids research,the fluid inclusion study has played an signif icant role in the study on the format ion environment of petroleum reservoir,t he relationship among t he coex ist ed organic &inor -ganic mineral deposit s in sediment ary basins.T his t echnique has been applied in this paper to study the petroleum reservoir and t he Sandst one T ype U ranium Deposit in t he northern Ordos Basin,the nort heast ern part of t he T arim Basin,t he M iddle -U pper Proterozoic strata in the L iaox-i Jibei Depression respectively.T hrough t he studies of the pet rography,transmit ted light -incident fluorescence,microthermomet ry,M icro -FT IR,isotopic dat ing t echniques of t he fluid inclusions,and t he analysis of t he t ect onics,burial history,t hermal evolut ion of the sedimentary ba -sins,the application of t he f luid inclusion st udy has been discussed on the qualit at ive and quant it at ive analysis of charact eristics,sources and episodes of ore -forming f luids,t emporal and spat ial relationships of fluid migrat ion and accumulation,and the f ormat ion and evolut ion of pet roleum reservoirs respectively.Key w ords:fluid inclusion petrography;micro -analysis of compositions;dating of inclusions;theory and applicat ion;sedimentary basins烃类流体活动贯穿于从烃源岩到圈闭的全过程,油气成藏史也是含油气系统内各地质要素和有机-无机作用在时间-空间上有机匹配的历史。
Abdominal Bloating and Distension

REVIEWAbdominal Bloating and Distension:What Is the Role of the MicrobiotaB.Issa •N.A.Wafaei •P.J.WhorwellReceived:12April 2011/Accepted:12July 2011ÓSpringer Science+Business Media,LLC 2011Abstract Most patients with irritable bowel syndrome complain of a sensation of an increase in pressure within their abdomen during the course of the day which is called bloating and,in approximately half of these individuals,this symptom is accompanied by an actual increase in abdominal girth,which is referred to as distension.The pathophysiology of these two phenomena is somewhat different and it is now recognised that a whole variety of overlapping mechanisms are involved.Some of these are potentially amenable to treatment by modification of the bacterial flora of the gut and this article reviews the evi-dence for this.Keywords Irritable bowel syndrome ÁBloating ÁDistension ÁMicrobiomeBackgroundPatients with functional gastrointestinal disorders,espe-cially irritable bowel syndrome (IBS),frequently complain of bloating and distension and it is not uncommon for themto report that these features often occur on a daily basis and,as a consequence,are especially bothersome.Another problem is that their management has always proved challenging,probably because,until recently,their patho-physiology has been poorly understood.However,the sit-uation is now beginning to change with the recognition that a whole variety of factors may be involved and,impor-tantly,that bloating and distension should be regarded as different but overlapping conditions.It is now suggested that the term bloating should be applied to the sensation of an increased pressure within the abdomen and that the term distension should only be used when this sensation is accompanied by an actual increase in abdominal girth.Recent research has indicated that in approximately 50%of patients reporting bloating,this sensation is accompanied by distension [1]and that there are subtle differences in the mechanisms underlying these conditions [2,3].Putative Causes of Bloating and DistensionResearch on bloating and distension has been hampered by the lack of availability of suitable methods of investigation but this has been changed by the advent of techniques such as the gas challenge technique [4,5],abdominal inductance plethysmography [6,7],abdominal and diaphragmatic electromyography [8,9],CT scanning [10],and no doubt magnetic resonance imaging will contribute in the future.The application of such methodology has resulted in the recognition that bloating tends to be associated with a phenotype characterised by increased visceral sensitivity [11],impaired gas handling [4],and diarrhoea [12],whereas distension is more often related to constipation [12],delayed gastrointestinal transit [12],weak abdominal musculature [13],and an abnormal accommodation reflexB.Issa ÁP.J.WhorwellNeurogastroenterology Unit,Department of Translational Medicine,University of Manchester,Manchester,UK N.A.WafaeiDepartment of General and Colorectal Surgery,Fairfield General Hospital,The Pennine Acute Hospitals NHS Trust,Bury BL97TD,UKP.J.Whorwell (&)Education and Research Centre,Wythenshawe Hospital,Manchester M239LT,UKe-mail:Peter.whorwell@Dig Dis SciDOI 10.1007/s10620-011-1834-4[8–10]where there is paradoxical contraction of dia-phragmatic and abdominal muscles in response to an increase in abdominal pressure.In addition,there is evi-dence that in at least a proportion of patients with IBS,the bacterialflora of the gut may be disturbed[14–16]and additionally,fermentation may also contribute to symp-toms[17]raising the possibility that these two factors may also contribute to both bloating and distension. Treatment Approaches to Bloating and DistensionAs a consequence of this evidence that bloating and dis-tension differ mechanistically to some extent,it follows that the success of treatment is likely to be enhanced if the appropriate pathophysiological abnormality is targeted in a particular individual.For example,relieving constipation is more likely to improve distension whereas for a patient with bloating alone,aiming to reduce visceral hypersensi-tivity is a more logical strategy.Unfortunately,the situa-tion is somewhat complicated by the fact that,at least in the UK,patients tend to describe their problem as bloating, irrespective of whether they are troubled by bloating or distension,but at least these pathophysiological observa-tions provide a framework for a systematic approach to managing these problems.Of the various pathophysiological mechanisms involved in bloating and distension that have been enumerated above,it seems reasonable to speculate that dysbiosis,gas handling,constipation,diarrhoea,visceral hypersensitivity, and fermentation might be amenable to modification by use of probiotics or antibiotics and there follows a discussion providing some evidence to support this view.The Therapeutic Potential of Antibioticsand ProbioticsThe notion that the microbiota of the gastrointestinal tract may be disturbed in patients with IBS has largely been prompted by two observations.First,for some patients with IBS there seems to be evidence of a low-grade inflamma-tory response within their gastrointestinal mucosa.Second, for others there is evidence of small intestinal bacterial over-growth(SIBO).Given that some probiotic bacteria have been shown to have a range of anti-inflammatory activity it is not surprising that their use has been advocated as a possible treatment for IBS.A relatively large number of controlled trials have been reported to date and,although their design has been rather variable,most have shown some evidence of a positive effect[18].However,it should also be noted that different symptoms seem to respond to different probiotics but in a significant proportion of studies an improvement in subjectively reported bloating has been documented.Evidence for SIBO has come from studies using breath testing techniques after carbohydrate ingestion and,depending on the substrate used,the repor-ted prevalence of the SIBO in IBS is somewhat variable [19].Nevertheless,these observations have led some researchers to speculate that antibiotics,especially if they are of the non-absorbable variety,might have therapeutic potential in IBS,and thefirst studies used neomycin with positive results[20].Subsequently,rifaximin has become the antibiotic of choice and there is now evidence that the use of this drug over a period of7–14days can reduce symptoms,including gaseousness and bloating,not only in the short term but also for a period of up to3months [21–23].Obviously,the prolonged use of antibiotics to treat a condition such as IBS could not be advocated,but if a short course of a non-absorbable antibiotic is beneficial with a substantial carry over effect,then this option might well have some utility.One of the problems with any research in this area has been that,until recently,evidence of the role of bacteria in conditions such as IBS has been hampered by the fact that it could only be investigated indirectly by the use of techniques such as breath testing,or directly by culture techniques which are impeded by the fact that only a relatively small proportion of the gut microbiota can be cultured[19,24,25].However,with the advent of molecular techniques,it is now possible to more accurately address this issue,and,after use of such approaches,reports are already emerging of variations in the microbiological profiles of gut bacteria in IBS[16, 26–32].Specific Evidence of the Benefit of Individual Antibiotics or Probiotics in Bloating and Distension Over the years,the Barcelona group have undertaken a series of elegant studies showing that compared with controls, patients with IBS have impaired handling of a gas load leading to gas trapping and the symptom of bloating[4].This observation suggests thatfirst,patients with bloating should avoid carbonated drinks and foods that tend to produce gas, and,second,that an attempt to alter endogenous gas pro-duction by modification of the bacterialflora is worthy of consideration,and that this could possibly be achieved by the use of an antibiotic or a probiotic.Certainly,some of the studies using rifaximin(Fig.1)have supported this view [21–23,33]and it is noteworthy that a reduction in bloating has been reported after use of some probiotics,for example VSL#3[34,35]and Bifidobacterium infantis35624[36], although whether this is a result of a reduction of endogenous gas-forming organisms has to be speculative and an alter-native explanation might be an effect on visceral sensation.Dig Dis SciVisceral hypersensitivity is one of the most well described pathophysiological abnormalities in IBS [37,38]and it has even been suggested that it might be a biological marker for the condition [39].Consequently,it is fre-quently regarded as a potential target for treatment,espe-cially by the pharmaceutical industry.The mechanism by which sensitisation is induced is not clear but it is of note that many patients date the onset of their IBS to an episode of gastroenteritis [40,41].It has been suggested that this could lead to sensitisation of the gastrointestinal mucosa as a result of persisting,low grade,inflammation or,alterna-tively,by a change in the gastrointestinal flora.It is,therefore,not surprising that it has been suggested that probiotics might have utility in reducing visceral sensitiv-ity.To our knowledge there have,so far,been no studies of this in humans but there are promising data in animals [42–44]indicating that it is certainly worthy of further exploration.Constipation [1]and delayed gastrointestinal transit [12]are associated with distension and it seems reasonable to suppose that improving constipation and hastening transit might lead to improvement of this problem.Consequently,it is of interest that the Barcelona group have shown that accelerating the transit of gas through the gut by adminis-tration of a prokinetic agent such as neostigmine can reduce girth [45].Thus,if transit could be hastened by administra-tion of a probiotic this could be an approach that might have potential in relation to reduction of abdominal distension.In physiological studies DN-173-010has been shown to accelerate gastrointestinal transit [46–49]and,in clinical trials,to reduce the subjective reporting of bloating [37].Therefore,this organism should,theoretically,have the potential to improve distension and this question has recently been addressed in a study using abdominal inductance plethysmography to objectively measure abdominal girth in patients with constipation-predominant pared with a matching placebo,the active probiotic,delivered as ayogurt twice daily,significantly reduced abdominal girth (Fig.2),and this was accompanied by an acceleration in both small and large bowel transit and an improvement in symptoms [50].It is also noteworthy that in an unrelated study,the frequency of the migrating motor complex was found to decrease in patients with IBS in whom the presence of SIBO was suggested by an abnormal lactulose breath test [51].Interestingly,motility seemed to be enhanced once this overgrowth had been eradicated [51].ConclusionIt seems that some probiotics and antibiotics may have a role in treating bloating and distension and this is possibly as a result of an effect on some of the mechanisms involved in the pathophysiology of these two common features of functional bowel disorders.Furthermore,it could be expected that as our understanding of the gastrointestinal microbiota and bloating and distension improves,even better control of these enigmatic symptoms might be forthcoming.Conflict of interest Professor Whorwell has served as an advisory board member or has received research funding from the following pharmaceutical companies:Novartis Pharmaceuticals,Glaxo SmithKline,Solvay Pharmaceuticals,Rotta Research,ProctorandFig.1A comparison of the effect of rifaximin or placebo on subjective global relief of symptoms in patients with abdominal bloating and flatulence.Taken from Ref.[22]Fig.2A comparison of the effect of bifidobacterium lactis DN-173010or placebo on the percentage reduction in maximum distension (maximum distension post treatment -maximum distension at baseline/maximum distension at baseline 9100)in patients with irritable bowel syndrome.Taken from Ref.[50]Dig Dis SciGamble,Danone Research,Astellas Pharma,Ironwood Pharmaceu-ticals,Sucampo Pharmaceuticals,Almirall Pharma,Movetis UK, Norgine and Chr Hansen.Boehringer–Ingelheim,Heel GMBH. 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The Analysis of the Application of Student-centered Teaching Model in English Teaching of Middle SchoolbyA thesis presented to the School of English Education ofXi’an International Studies Universityin partial fulfillment of the requirementsfor the degree ofBachelor of ArtsMay 20, 2012Class:Advisor:AcknowledgementsI would like to express my thankfulness and gratitude to my instructor Fan Guifang, for her valuable suggestions, hearty encouragement and careful and patient instruction in the completion of this thesis. Instructor Fan’s profound knowledge, creative advice, and her insights into the teaching and classroom instruction helps me to step into the research field and makes my words possible and better through modifications.I would also like to express my gratitude to advisor Zhang Xinyue, she helped me a lot in collecting the materials and how to write a paper. I have to say thanks to my group members, my roommates and my esteemed leaders. Without their support and encouragement, I would not complete this paper in time.浅析以学生为中心的教育模式在中学英语教学中的应用摘要:在中国,自从执行改革开放的政策以来,英语教学取得了很大的进步,英语教师也进入了一个改革的新时代,为了适应中国改革发展的需要,英语教学的很多方面都需要改进。
在当前素质教育的前提下,英语教学已改变传统的以教师为中心的教学法。
这篇论文展示的是“以学生为中心”教学理念,其核心和强调的重点是教学的中心己经从老师的身上转移到了学生身上,在课堂上,学生应该十分的积极活跃,而不是被动地接受老师提供的知识,所以,“以学生为中心”教学理念受到了英语教师和学生的欢迎,而且成为大家瞩目的焦点。
本文主要探讨了以学生为中心的教学法的目的,基本原则以及这种教学法在英语课堂的实际应用。
这种教学法不仅能够提高学生的学习积极性,发展学生的交际能力,更重要的是能够培养学生的自主、自力、积极探索的精神。
在教学过程中教师应该遵循“以人为本”的教育方针,注重学生的需要,因为教育的最终目的是育人。
关键词: 以学生为中心的教学法; 语言教学; 教学模式The Analysis of the Application of Student-centered Teaching Model in English Teaching of Middle SchoolAbstract:In China, since the execution of reform and opening policy, the teachers have made great achievements in English teaching,the English teaching has entered another new century-the times of innovation. In order to cater for the need of national fundamental reform, many aspects in English teaching should be changed. Under the guidance of the “quality-oriented education”, we have changed the traditional teacher-centered approach in English Language Teaching (ELT). This paper presents “Learner-Centered”,the new concept of teaching under the instruction of constructive learning theory in Junior Middle School. The emphasis of foreign language teaching has shifted to students from teachers. The students should be more active in class instead of passively receiving information which the teachers provide. So “Learner-Center ed” has become the focus, and is welcomed by English teachers and students. Then, this paper sets out to examine the objective of the Learner-centered Approach (LCA) and most importantly, the basic principles and the application of this approach in ELT. The learner-centered approach can enhance students’ motivation, develop their communicative competence and cultivate their autonomy. A call for teachers to pay more serious attention to treating students as whole persons rather than receptacles in ELT for the ultimate goal of the education is to train independent learners.Key Words: a learner-centered approach; language teaching; teaching methodTable of Contents1.Introduction (1)2. Present Problem of ELT in China (3)3. The Theory of Student-Centered Teaching Model (4)3.1 The definition of Student-Centered Teaching (4)3.2 The Perspectives of Learner-Centered Teaching Model (4)4.Approaches to LCA in ELT Class (5)4.1Fostering the Learner’s Autonomy (5)4.1.1Raising the Students’ awareness for Learning Autonomy (5)4.1.2Promoting the Students’ abilities to Select and Use Strategies (6)4.1.3Testing Approaches to Monitor the Autonomous Learning (7)4.2Creating the Humanistic Teaching Atmosphere (8)4.2.1 Teachers’ evaluation on Students (8)4.2.2 Learner's Needs and Affection from Teacher (9)4.3 Using Cooperative and Motivated Learning Methods (11)4.3.1 Offering the Students Pairs and Groups Work (11)4.3.2 Providing the students enough space and time... . . . . . (12)4.3.3 Gettin g the Whole Class Involved in the English Activities (13)5. Paying attention to the below points by teachers (14)5.1 Time control (14)5.2 Choice of content and activities (14)5.3 Out-of-class interaction with students (15)6. Conclusion (16)References (17)1. IntroductionBased on a large scaled survey, the paper describes the current teaching models in English Language Teaching class in Middle school, analyzing the development that impede the application of learner-centered teaching approach. Finally, the paper provides suggestions for teachers on the application of learner-centered approach in English language teaching.The current teaching style can be traced to ancient times, when teachers were expected to pass on the truth, impact knowledge and solve problems. This kind of traditional teaching, teacher- centered approach has ignored the position of learners i n the class for a long time. The teacher has the absolute authority while student’s autonomy is totally deprive of. Student were supposed to sit quietly and to write down what teachers say and to obey all the rules set by teachers in class. Otherwise, they will be labeled as bad students.Nowadays, the demands of a rapidly changing information society stress the importance of flexible competencies. Thus English has become the basic communication tool. English learners need to be fluent in both spoken and written English. So, it is necessary that we change the teacher- centered approach in English language teaching. Student should be put at the center of the learning process and their needs should be the first point that teacher should keep in mind.It is believed that the learner- centered approach can enhance student’s motivation, develop their communicative competence and cultivate their autonomy.A call for teachers to pay more serious attentions to treating students as whole persons rather than receptacles in ELT for the ultimate goal of the education id to train independent learners.As a teacher of English, it must be thought over about what should be taught and how to teach the students in the classroom. What strategies should the teacheradopt and what strategies should be based on. There is a great worth to do some research on this topic.Form this topic, it can help the English teachers widen their knowledge and it can improve teacher’s techniques by designing learner- centered in the classroom, so that they can enable learners to communicate more efficiently in a foreign language, it can suggest activities through which teacher can help learners to use English in the real communications. Concretely speaking, by advocating learner- centered in the classroom, the paper aims to f oster the learner’s autonomy, to create the humanistic teaching atmosphere and use cooperative and motivated learning methods2.Present Problem of ELT in ChinaFor decades Chinese teachers have been quite used to the traditional way of teaching foreign language. Teachers are constantly pre-occupied by their own role what they should be doing, and what their students think of them. In the teacher-centered approach emphasis is placed on teaching instead of learning. Teachers appear as controllers, who are in complete charge of the class. They try to put everything into students’ heads and students are seen as receptacles to be filled with knowledge. This is sometimes referred to as “the jugs and mugs” theory (Naiman, 1978). The teacher is seen as having a large “jug” of knowledge which is poured into the student’s“mug”or receptacle. Some linguists describe this as the “banking”conception of education, where learners are like bank accounts into which deposits are regularly made and withdrawn later for specific purposes such as examination. This way of teaching has a lot of problems.The present era is one with an explosion of knowledge and information. Then, more is demanded of teachers than ever before. Moreover, many state-owned enterprises set high demands for the graduates’ language level. The social circumstances also exert great pressure on the students.Teachers should realize that their responsibilities of “passing on the truth, impartknowledge and solve problems” (Hanyu, 1999: 2)are far from enough. What teachers should do is to equip students with the means to cope with problems by themselves. At the same time, good teachers should manage to let students go of their hands and start to take some responsibilities for their own learning. As for students, they should be fully aware of the importance of independent thinking. They should develop not only a high level of competence in reading, but also an intermediate level of competence in listening, speaking and writing.Taking all these factors into consideration, we find it necessary to abandon the long-standing teacher-centered way of teaching. In the teacher-centered classroom, students are treated as passive recipients. They do not have to take any- initiative, just waiting there to be filled with knowledge. Both the teachers and the students have realized that what they are teaching and what they are learning are “dumb English”(1987) which can not be applied in real life. The teacher-centered approach can no longer fit in with the present situation. In order to answer the call for the “quality-orientation”(Cohen, 2001), teachers should adopt the learner-centered approach in English Language Teaching (ELT). This approach puts learner at the center of the learning process and attaches great important to learners’ needs. Students are seen as being able to assume a more active and participatory role than they did in traditional approaches.3. The Theory of Student-Centered Teaching Model3.1 The Definition of the Student-Centered TeachingStudent-centered teaching focuses on what the student is learning, how the student is learning, and the conditions under which the student is learning, whether the student is retaining and applying the learning. The distinction between teacher-centered and student-centered is made as a way of indicating that the spotlight has shifted from the teacher to the student. In student-centered instruction the action focuses on what the student are doing not what the teacher is doing.Student-centered education also creates an environment that supports the individual as a whole person. It attempts to meet the individual needs of a board range of learners who have different ways of knowing, skills and cultural background.3.2 The Perspectives of Learner-Centered Teaching ModelNunan (1991:178) defines the learner-centered as follows“A learner-centered teaching model is based on a belief that learnerswill bring to the learning situation different beliefs and attitudes aboutthe nature of language and language learning and that these beliefs andattitudes need to be taken into consideration in the selection of contentand learning experiences. The approach contrasts with the‘doctor-knows-best’ approach which, while it might acknowledg e thatlearners have different preferences and beliefs, discounts these on thegrounds that the teacher is the expert and that the learners’ views arerrelevant.”In the LCA, the learner should be seen as being the center of the educational process. For the teaching institution and the teacher, this means that instructional programs should be centered around learners’ deeds and that learners themselves should exercise their own responsibility in the choice of learning objectives, content and methods as well as in determining the means used to assess their performance. Learners are not merely passive recipients of subject matter devised by some educational authority, but have a wide experience of life which can be brought to bear in the learning process. Learners are less likely to be interested in subscribing to the ‘banking principle’(Williams, 1997) they want to gain the communicative and linguistic skills they need to carry out real-world tasks. It is believed that only the learner can learn while the teacher can just help and advise.Mark B Yeary (2002) believed that Learner-centered education is a promising model that relies on two complementary components: Placing more responsibility in the hands of the students; Requiring the instructor to serve as the “presenter orfacilitator of knowledge,” rather than the traditional “source of all knowledge.”4. Approaches to LCA in ELT Class4.1 Fostering the Learner’s Autonomy4.1.1 Raising the S tudents’ Awareness for Learning AutonomyThe findings suggest that the desire of middle school students for autonomous learning is relatively high. They are willing to be free from being dependent on teachers though they grow up laden with traditional Chinese culture in such an authoritarian society wherein “obey” is unconditioned. However, there are a number of middle students show poor awareness of learning independent of the teachers. Life would be marvelous for teachers if all students wanted to learn (Biggs 1999:85; cited in Cheung, 2001: 55). According to Biggs, students are only motivated to learn things that are important and meaningful to them. Thus autonomous English learning should be valued, strengthened and focused on throughout the whole process of teaching and learning to fully develop the student potential for LA (Learning Autonomy). Most importantly, teachers need to loosen their tightly control of the classroom and the students should be provide more chance for them to take on more responsibility for their own learning.The primary objective of language learning is to help students become more autonomous, so that they will be equipped with the skills to go about their own learning. In fact, some students are not as ready as others for independent language learning. And to change one’s view of learning requires a flexibility that not everyone has. In order to help students become autonomous, it would be more effective to provide training and make it integral part of the English teaching. Dickinson (1987:2) believes the way forward against learner resistance is to train learners toward greater autonomy and aim toward a gradual development to full autonomy. Nuan (1996:13) rightly points out that “some degree of autonomy can be fostered in learners regardless of the extent to which they are naturally predisposed to the notion”. Training activities can be incorporated systematically in the classroom to helpstudents become more aware of the learning process, more ready to take charge of their own learning , essentially, students can be helped to come to terms with their strengthens and weaknesses, to learn a language efficiently in ways that are compatible with their personalities. Training would benefit the “lazy” students, too, who might feel that they are doomed to failure in language learning due to their own laziness, by increasing their self-confidence and self-esteem, changing their beliefs and attitudes towards their own role in language learning. It can certainly encourage the students to become aware of the many factors (including the personal, social, and political), which affect their learning, and to re-evaluate the learning approaches and strategies that work best for them within their specific context.Through consciously training learners take the initiate in learning, one of the fundamental prerequisites for autonomous because they learn more thing, and learn better than do people who sit at the feet of teachers, passively waiting to be taught. They enter into learning more purposefully and with greater motivation to retain and make use of what they learn better and longer.4.1.2 Promoting the S tudents’ Abilities to Select and Use learning StrategiesFrom data analysis, it is known that middle school students, juniors in particular, are extremely incapable of applying metacognitive strategies, which is crucial in autonomous learning. The important role of metacognitive strategy played in successful learning is that controls the using of the cognitive strategies. Since no one has innate self-management and self-determination, especially some Chinese students with tendency to act relying on other s’ assistant instead of developing on them. It is important to promote students’ awareness and control of effective learning strategies and discourage the use of ineffective ones in English teaching.Strategies virtually promote autonomy in many aspects of learning. Only when students learn how to learn, in other words, have the abilities to select and use strategies can they diagnose their own learning strengths and weakness and become more autonomous. First of all, students’strategy awareness, refers to language learning awareness (knowledge about some of the factors that influence the languageprocess)(Dickinson’s 1992)is the fundamental prerequisite of applying strategies available. To be proficient in the use of a aboard range of metacognitive learning strategies, students should first become more aware of and familiar with the general idea of metacognitive learning strategies and the way such strategies can help them accomplish various learning tasks.Strategies-based Instruction (SBI) suggested by Cohen (2001:81) is viewed as a most effective kind of strategy training for practice. The SBI aims to assist students in becoming more effective learners by allowing them to initializes the language learning experience and gain more confidence in their ability to learn. It can also enhance students’ effort to reach learning goal because it encourages students to find their own pathways to success and thus promotes the students autonomous learning in English.The ultimate goal of strategy training is empowering students by allowing them to take control of their learning process. Teachers can further encourage independent strategy use by encourage the students to take responsibility for the selection, use, and evaluation of the various strategies that they have been taught.4.1.3 Testing Approaches to Monitor the Autonomous LearningIn middle school, learning objectives are often fixed at the outset, limiting any individual goal orientation, and teachers’assessments leave students little room for self-assessment. Most importantly, large classes and lack resources also make an individualized approach to learning difficult. All these demotivate students who cannot see any clear progress and goal to aim for.English language teaching is virtually not restrict to transmitting linguistic knowledge about English, furthermore, teaching students how to learn independently should also be integrated into it. Self-evaluation is proved to be an effective means available. It is therefore very necessary to promote the students’abilities for self-assessment and self-monitor to provide sensitive awareness. It is also important to help students, especially those who are passive ones to be more active to realize that they have the ultimate responsibility for learning to locate their own strengths and weakness and then get them to think about what they need to do, in order to performwell in English learning. Then self-assessment may be an effective means available.Though objective self-evaluation the students are helped to perceive their own progress and encouraged to see the value of what they are learning. And as Godwin(1797) pointed out “he best motive to learn is a perception of the value thing learned”(cited in Hanis: 1997). As an individual’s learning awareness grows, the potential for the student’ AEL increases.To conduct self-assessment, two useful instruments are used commonly: self-diagnostic questionnaire and learner diary or booklet to be integrated into everyday classroom activities three or four times a term.4.2 Creating the Humanistic Teaching Atmosphere4.2.1 Teachers’ Evaluation on StudentsEvaluation in English learning is a crucial aspect, which provides students with strengths and weaknesses as well as direction for future learning. In middle school, senior students show slight disagreement with teacher evaluation on them while juniors show great agreement with dependence on teacher evaluation that focus on outcomes than seniors. Seniors hope to evaluate their learning on their own mostly focus on their learning process in addition to the outcomes. As most psychologists and educators tend to agree that “Learning is a process by which behavior is either modified or changed through experience or training.”In other words learning refers not only to an outcome that is manifestly observable, but also attitudes, feelings and intellectual process that may not be so obvious.The reason that they are incapable of self-evaluation may be that they have experienced few learning contexts, which encourage them to exercise individual self-assessment. In reality, teachers are in control of the area of assessment and the students do not own the real opportunity to conduct self-assessment. A key learning strategy for autonomous learning in middle school is self-assessment. It is in need of new perspectives on progress, enabling students to monitor their progress and relate learning to individual needs. The key point here is that whether the teachers are willing to provide the opportunity for the students to access their own progress and thus help them to focus on their own learning and make them see their learning inpersonal terms.Only when students exercise a variety of learning strategies and higher order thinking skills, can they benefit more. Teacher assessment is virtually impossible to continually monitor individual performance correctly, so combining self-assessment with teacher assessment is particularly importantly. In this way, self-assessment helps to compensate by providing continuous, personalized and formative element of assessment. Once being allowed, self-assessment by no means guarantees that students do sow the seed of an individual focus on learning. And periodically review own progress or to coincide with periodic teacher assessment when necessary.4.2.2 L earner’s Needs and Affection from TeacherL earners’ affection has strong effect on their learning process. If their affection towards the learning is positive, the study will come to a positive result and vice versa.According to the survey, current ELT class is teacher-oriented and students are positioned in a relatively less autonomous role. Their thoughts, feelings and emotions are easily to be ignored and controlled by the teacher. With less autonomy, students' interests in study also decrease, thus the study becomes inefficient. To give more concern to learner's affection, a more humanistic study environment is required.The learner-centered approach, giving more choices and freedom to learners, is much more humanistic than the teacher-centered one. It emphasized the importance of the inner world of the learner. Maslow (1968) suggested that children should be allowed to make many choices about their own development. Although parents and teachers’ roles are guiding children to make right decisions, they were not supposed to shape or control the way their children develop. What they should do was to give advice and to help them to grow.Learners should be encouraged to think and not to be penalized for being different and creative. Classroom activities should be challenging and encourage curiosity in order to help learners realize their full potential. The primary function of education is to enable learners to develop as individuals in their own right and thereby achieve self-actualization.Stevick (1990) is another proponent of humanism in language teaching. He came to the conclusion that success or failure in language teaching depends not so much on whether one adopts inductive or deductive techniques for teaching grammar, nor whether one engages in meaningful practice rather than pattern drills, but in the extent to which one caters to the learner’s affective domain. In this learner-centered view of language development, the emphasis at all times should be on the learners, not on the teacher. In the mean time, Stevick also points out that learner-centeredness does not imply that teacher should abandon the classroom to the learners, that there are a number of functions that teacher should perform. This is in accordance with what we have learned from our interviews with students and teachers. Although the teacher-centered approach is not very welcome among students, they do not totally deny the benefits and necessity brought by the approach, especially when facing the pressure from upcoming exams. But if the teacher is too dominant in the class, learners' affective filter will filter a lot of “input”,with which learners’“output” will also be reduced. Being exposed in a more humanistic study environment will help learners abstract more input more easily, happily, and willingly.Being taught in a more humanistic way, learners are treated as a whole person and the whole-person involvement in the learning process is concerned really. It can help minimize learning anxiety and enhances personal security by creating a more friendly study environment.To give real concerns to learner’s needs and affection, a learner-centered ELT class:1 .Creates a sense of belonging2. Makes the subject relevant to the learner3. Involves the whole person4. Encourages a knowledge of self5. Develops personal identity6. Encourages self-esteem7. Involves the feelings and emotions8. Minimizes criticism9. Encourages creativity10. Allows for choice11.Encourages self-evaluation(Williams, & Burden 1997: 38)Therefore, a learner-centered approach, which acknowledges that man is is more humanistic and makes learning more cheerful and vital and easier for learners.4.3 Using a Cooperative and Motivated Learning Methods4.3.1 Offering the Students Pairs and Groups Work.Bruton and Samuta(1980) found that, contrary to popular belief learners in small groups were capable correcting one another successfully. Porter (1983, 1986) found (also contrary to popular opinion) that learners do not produce more errors or learn each other’s mistake s when working together in small groups. Learners in pairs engage more modified interactions. What is more, the findings confirm the importance of the nature of pair interaction for the learning opportunities available to the students. In a language classroom, especially in a large size of a language classroom, where a language teacher cannot ensure that all the individual students can have adequate opportunities to practice English in terms of all language aspects, he/she can easily organize the students in pairs to interact for a great variety of work including listening, speaking, reading and writing.Organize students in a reasonable way, most teachers let their students form their pairs or groups at will. Namely, students can choose their own partners in pairs or groups as they like. The most distinct advantage of this method is students may feel relaxed and ease since they can stay with their favorite partners in pairs or groups. In this case; Students willingness to practice English can be maximized. On the one hand, they are eager to show their language ability among their acquaintances; on the other hand, they desire to share opinions with their collocutors about some topics they are interested in.In general, the teacher ought to have a good knowledge of what is happening inhis/her class. Plan the appropriate pair work or group work tasks. The type of activity decides students’ zest to engage in the activity and the effect of language development. If the activity appeals to students, the classroom climate may be very decent to interact in pairs or groups. Then students are all involved in the activity and the teacher does not have to bother to keep the class in discipline. The sensible classroom climate for students to practice English largely depends on the types of pair work or group work tasks.4.3.2 Providing the Students Enough Space and Time to Nurture Their IndividualityIndividual students have their own personalities, study habits and methods that require respecting and encouraging. Then in some cases the teacher must let students work on their own at their own pace, providing them with enough space and time to nurture their individuality. Different from pair work and group work, individual work does not involve the active interaction but it is inclined to be quiet. Such quietness is badly needed by the students who hope to have their own space and time to mediate. It is no doubt that continuous pair work or group work deprives students of the opportunities to develop themselves individually. In addition, individual work can help students get rid of the pressure and tension from pairs or groups when students have to do some face-to-face interactions. The teacher can walk around the classroom to instruct individual students who need some special help or communicate with some individual students without disturbing others now and then. Even though individual work is relatively hard for the teacher to monitor, it is still popular to the teachers who do not bother to group students or when they feel diversity in classroom management is needed.4.3.3 Getting the Whole Class Involved in the English Activities.In order to get all the students involved in the English interaction, the teacher often stands in front of the classroom and start interaction between the teacher and the whole class. The most common way the teacher adopts in class is to explain language bits first and then work with the whole class. This way is most frequently used to learn sentence patterns or drills. To ensure that accuracy can be effectively achieved,。