Via introduce
introduce的用法总结大全
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文档下载后可定制修改，请根据实际需要进行调整和使用，谢谢!并且，本店铺为大家提供各种类型的经典范文，如英语单词、英语语法、英语听力、英语知识点、语文知识点、文言文、数学公式、数学知识点、作文大全、其他资料等等，想了解不同范文格式和写法，敬请关注!Download tips: This document is carefully compiled by this editor.I hope that after you download it, it can help you solve practical problems. The document can be customized and modified after downloading, please adjust and use it according to actual needs, thank you!In addition, this shop provides various types of classic sample essays, such as English words, English grammar, English listening, English knowledge points, Chinese knowledge points, classical Chinese, mathematical formulas, mathematics knowledge points, composition books, other materials, etc. Learn about the different formats and writing styles of sample essays, so stay tuned!introduce的用法总结大全introduce的意思vt. 提出；介绍；引进；作为…的开头introduce的用法1. introduce表示“介绍”时的意思是to tell two or more people who have not met before what each others’ names are （告诉两个或多个原来未曾见面的人他们彼此的名字），或者是to tell the audience the name of the person who is going to speak or perform（告诉观众讲演者或演员的名字），也就是说，introduce 表示“介绍”时，主要用于介绍两个不认识的互相认识，或是向听众或观众宣布并介绍演讲者或广播、节目等的细节。
维亚维解决方案 OneAdvisor 800 产品数据表说明书
VIAVI
OneAdvisor 800
Modular test platform designed for use in the installation and maintenance of fiber, wireless and transport applications.
Size and weight (Mainframe)
Weight2ຫໍສະໝຸດ 0 kg (4.4 lb) without module (including battery)
Size (W x H x D)
270 x 170 x 60 mm (10.6 x 6.7 x 2.3 in) without module
ONA-800A-MF2G-T
OneAdvisor ONA-800A Mainframe with Display - no WiFi and Bluetooth Radios
Solution Hardware Modules
E81FMC1
Fiber module receptacle for E8100-series fiber modules
C2K-EMPTYMOD
Empty module to cover an unused expansion port
ONA-800A-DISPL ONA-800A-DISP-F ONA-800A-DISP-T
OneAdvisor Display
ONA-PMVFL
Power Meter and VFL Mainframe Module for OneAdvisor 800
AC Power with battery charging Battery discharging condition
introduce myself
自我介绍用语大全之问候类1.Good morning everyone.大家早上好。
2.Good afternoon, ladies and gentlemen.先生们，女士们下午好。
3.Good evening, teachers and fellow students.老师们，同学们晚上好。
4.It’s my great honor to introduce myself to you here.很荣幸在这儿向大家作自我介绍。
5.It’s my pleasure to introduce myself to you here.我很高兴在这儿向大家作自我介绍。
6.I’m very happy to introduce myself to you here.我很高兴在这儿向大家作自我介绍。
7.I’m very glad to introduce myself to you here.我很高兴在这儿向大家作自我介绍。
8.I feel very honored to introduce myself to you here.我感到很荣幸在这儿向大家作自我介绍。
9.It is a great pleasure for me to introduce myself to you here.我是如此的高兴在这儿向大家作自我介绍。
10.It is a privilege to be speaking to you today.今天能跟你谈话真是我三生有幸。
11. I am very proud to be addressing you this evening.今晚能在此应邀讲话我深感荣幸。
Sample1:My name is ________. I graduate from ________ senior high school and major in ________. There are ________ people in my family. My father works in a computer company. And my mother is a housewife. I am the youngest one in my family.In my spare time, I like to read novels. I think reading could enlarge my knowledge. As for novels, I could imagine whatever I like such as a well-known scientist or a kung-fu master. In addition to reading, I also like to play PC games. A lot of grownups think playing PC games hinders the students from learning. But I think PC games could motivate me to learn something such as English or Japanese.My favorite course is English because I think it is interesting to say one thing via different sounds. I wish my English could be improved in the next four years and be able to speak fluent English in the future.Sample1:I am . I was born in . I graduate from senior high school and major in English. I started learning English since I was 12 years old. My parents have a lot of American friends. That’s why I have no problem communicating with Americans or others by speaking English.In my spare time, I like to do anything relating to English such as listening to English songs, watching English movies or TV programs, or even attending the activities held by some English clubs or institutes. I used to go abroad for a short- term English study. During that time, I learned a lot of daily life English and saw a lot of different things.I think language is very interesting. I could express one substance by using different sounds. So I wish I could study and read more English literatures and enlarge my knowledge.Sample3:My name is . There are 4 people in my family. My father is a Chemistry teacher. He teaches chemistry in senior high school. My mother is an English teacher. She teaches English in the university. I have a younger brother, he is a junior high school student and is preparing for the entrance exam.I like to read English story books in my free time. Sometimes I surf the Internet and download the E- books to read. Reading E- books is fun. In addition, it also enlarges my vocabulary words because of the advanced technology and the vivid animations.I hope to study both English and computer technology because I am interested in both of the subjects. Maybe one day I could combine both of them and apply to my research in the future.Sample4:My name is . I am from . There are people in my family. My father works in a computer company. He is a computer engineer. My mother works in a international trade company. She is also a busy woman. I have a older sister and a younger brother. My sister is a junior in National Taiwan University. She majors in English. My brother is an elementary school student. He is 8 years old.Because of my father, I love surfing the Internet very much. I play the on-line game for about 2 hours every day. I wish I could be a computer program designer in the future. And that is why I am applying for the electronics program in your school.Sample5:From a middle class family, I was born in Hsin Ying, Tainan on October 10th, 1965. My father is a civil official at Tainan City Government. My mother is a house wife good at cooking. Although I am the only child of my parents, I am by no mans a spoiled one. On the contrary, I have been expected to be a successful man with advanced education. I study hard at school. Besides texts knowledge, journalism is my favorite; whenever reading, my heart is filled with great joy and interesting.“Being good is must; successful, however, is plus.” Father adopts the idea of his father. Especially in military service, I realized it more precisely. People said: Military service makes a boy to man, I agree that.I realized the importance of English and began to study diligently when I was eighteen. I did not start in my early age, but I hope that I could pass the test of General English Proficiency Test. And this is my best wish at the moment.Sample6:After completing my military service, I have been looking for a challenging goal for me to achieve. And I found that the Intermediate of General English Proficiency Test fits my new achievement properly.I graduated from Taipei Commercial Junior College, majored in business administration. Instead of spending much time in playing, I devoted myself to my studies and paid attention to all meaningful things happened in daily life. By the way, I learned a lot from Mr. Wang, the professor of my business class. He is my good friend till now an often gives some appropriate suggestions toward my problem confusion.My father is, in the same way, a good consultant to me. As he said: I am in poor education, little for you; to clarify, what he have given is far beyond his words, I do think so. I was born in a country of Ping Tung Country, farming is our career of generations. There are four people in my family, Mother is housewife and my brother is a student of an Agriculture College.I am optimistic and active, and I am confident that I can pass the test. Thank you for your precious to read my autobiography.Sample7：1、Good morning/afternoon/evening, my name is . It is really a great honor to have this opportunity/chance to introduce myself. I would like to answer whatever you may raise, and I hope I can make a good performance today.上午好/下午好/晚上好！我的名字叫……。
introduce的用法和固定搭配
introduce的用法和固定搭配1. "Introduce oneself"，就像你去参加一个新活动，要大大方方地说：“Hi，大家好，我是[你的名字]呀！”比如：I need to introduce myselfto the new team.（我得向新团队介绍下自己。
）2. "Introduce something to someone"，哎呀，这就好像你发现了一个超棒的东西，兴奋地跟朋友说：“嘿，我给你介绍个好东西！”例如：He introduced the new idea to his classmates.（他向他的同学们介绍了这个新想法。
）3. "Be introduced to"，仿佛你被带到一个新的世界，有点新奇又有点期待，像这样：I was introduced to the world of jazz.（我被带入了爵士乐的世界。
）4. "Introduce A to B"，就如同把一个人和另一个人牵上线，比如：She introduced John to Mary. （她把约翰介绍给了玛丽。
）5. "Introduce with"，这就好似用一种特别的方式来开场，像：He introduced the speech with a joke.（他用一个笑话来开始他的演讲。
）6. "Introduce into"，好比把什么东西带入某个领域，例如：They introduced new technology into the factory.（他们把新技术引入了工厂。
）7. "Make an introduction"，这就好像郑重地来一个开场介绍，如：She made an introduction at the beginning of the meeting.（她在会议开始做了一个介绍。
（完整版）打印版刘一男考研核心词根词缀
（完整版）打印版刘一男考研核心词根词缀刘一男考研核心词根词缀-必背版aer(o) = air空气（元音变化）aerial空气的/ aeroplane飞机alt = high高（Altai阿尔泰山）altitude高度annu(enni) = year年（an一n年）anniversary周年纪念/ annual年度的arch(y) =长者、统治(变化自ancient) anarchy无政府状态/ monarchy君主政体astro(aster) = star星astrology占星术/ astronomy天文学audi(audit) =hear听 audience听众/ audit旁听、审计auto-=self自我autocrat专制者/ automobile汽车bio(bi) = life生命（bio=body） biology生物学/ biotic生命的、生物的cardi = heart心(来自cord=core-核) cardiac心脏的/ cardinal 衷心的cess (ceed, ced) = go行走 precede领先/exceed超过/ process 过程cert = certain确定的certify证实/ certificate证明书circ=ring环形 circus马戏场/circulate流通、流传cosm(o) = world 世界 cosmic宇宙的cred = believe相信credible可信的/credulous轻信的/dent = tooth牙齿 dentist牙医/ trident三叉戟dict = say说 dictation口述、听写/ dictator独裁者duct =教导、引导educate教育/ introduce介绍ego = I我（e=I）egoist自我主义/egocentric自我中心的equ = equal相等的equivalent相等的/ equator赤道flu = flow流动 fluent流利的、流畅的/ influence影响fus = pour灌注 refuse回绝、拒绝/ confuse使…糊涂、混乱geo = earth地(G-Gaea该亚) geography地理/geometry几何/ geology地质学gram = write grammar语法/ diagram图表/ telegram电报graph = write photograph照片/telegraph电报机/graphics制图法habit = dwell居住（h-home-house-hole）habitant居住者/ inhabit 居住于hale = breathe呼吸(h-呼吸的声音) inhale吸/ exhale 呼hydro = water水（hy-氢）hydroelectric水电的/ hydrology水文学ject = throw投掷（j-投射）project投掷；计划/ inject注射/ reject拒绝junct = connect连接 junction结合（点）/ conjunction 连接词/adjunct附属的leg, legis = law法 legal法律的/legislate立法lingu = language语言 linguistic语言学/multilingual多语言的liter = letter文字 literate识字的/ literature文学/ literal字面的loc = place地方 local地方的/ locate放置/ dislocate脱位log = speak说 dialogue 对话/ apology 道歉/ logic逻辑lun = moon月亮（lun-轮） lunar月亮的/ superlunary 天上的mar = sea海（m-mother-江河之母）marine 海上的/ submarine潜水艇metr = measuring测量（metre=meter-米）geometry 地理/ diameter直径mini = small小minify使缩小/ minimum最小量/ miniature微型物nov=new新的（o=e//v=w）novel新奇的；小说/ innovate创新/ renovate革新nut = nourish营养(nut-nat-生育、哺育)nutrition 营养/malnutrition营养不良pel = push推（p-掌）propel推动/ expel驱逐/ repel反击port = carry运 portable可携带的/ import进口/ porter搬运工pose = put放 expose使暴露/ compose编，创作/ oppose反抗pure = pure纯净的(变化自poor) purify净化/ purity纯净/ impurity不净rect = right正、直 correct正确/ rectify纠正/ erect竖立rupt = break破(r-小草、突、破) interrupt打断/ disrupt瓦解/erupt喷发scend(s) = climb攀爬（scale-攀登）ascend上升/descend下降/ transcend超越scrib(pt) = 写（scr-爪子）describe 描写/scripture手稿/ subscribe订阅sect = cut切割 insect昆虫/ bisect二等分/ dissect解剖sent (sens)= sense sentiment 感情/ consent同意/ sensation 感觉sole = alone单独 solo独唱/solitary单独的/desolate荒凉的son = sound声音 sonic声音的/ resonant回声的/ stereosonic 立体声的spir = breathe呼吸(sp-喷、嘴) conspire同谋/inspire鼓舞/ expire终止struct = build建造（str=stere-立体的）structure结构/construct建造/destruction破坏tele = far远（t-tend-延伸） telescope望远镜/ telegram电报/television电视thermo =warm热（th-h-w）thermos热水瓶/thermochemistry热化学tract = draw拉(dr-“拽”) tractor拖拉机/attract吸引/contract合同vert = turn转subvert颠覆/ divert转向/ reverse翻转vis, vid = see看 visible可见的/advise建议/ evident明显的viv = live 活 survive比…活得长/ revive复活/ vivid生动的1 ag 做,动由 act(动作)演化而来, c/g 互换.2 agri 田地种田 (也做 agro, agr)由 acre (亩)演化而来,c/g 互换,元音字母互换.3 ann 年也做enn1 简化于annual 每年的年度的 manual 有手册,因为man 有手工的意思.4 audi 听(audio)5 bel 战争B有板子,棒子的意思,.6 brev 短Br 繁殖,分裂,分支branch来自br 解释为树枝bridge 来自 branch 因为早期的桥用较大的树枝制成的brief 来自 bridge (桥缩短了距离)brev 来自 bref (f/v 浊清互换)7 ced 走C 代表走,跑的意思,由car, bar, jar一组单词比较得出,单词的含义集中在开头的辅音字母.8 cept 拿取C 代表抓的意思,由单词(catch,hatch,watch,patch)比较而出。
introduce的汉语是什么意思
introduce的汉语是什么意思introduce的汉语意思英 [ˌɪntrəˈdju:s] 美 [ˌɪntrəˈdu:s]第三人称单数：introduces现在分词：introducing过去分词：introduced过去式：introduced基本解释及物动词介绍; 引进; 提出; 作为…的开头相关例句及物动词1. Allow me to introduce my friend Miss Wood to you.允许我向你介绍我的朋友伍德小姐。
2. The chairman introduced the speaker to the audience.主席把讲演者介绍给听众。
3. He introduced his friend to me.他把朋友介绍给我。
introduce的单语例句1. The company also plans to introduce 15 new models to China by the end of 2015 in order to tap the growing auto market.2. This free exhibition will introduce the 16 districts and counties of Beijing until next May, by providing a panoramic view of each area.3. The CAAC began to introduce aviation police late last year when it was feared that several Chinese flights risked being hijacked.4. GM will introduce the Cadillac CTS and CRX limousines in its factories in Shanghai later this year.5. The bureau warmed that if publishers fail to comply, it will call in tenders " to introduce more competition into the monopolized textbook market ".6. Some politicians and social activists have been calling for the government to introduce massive social program to address this thorny issue.7. We shall introduce scale exploitation, raise the level of intensiveness and eliminate backward and scattered mining capacity.8. It used the loan to produce The Lion King, reducing its capital pressure to introduce other productions to the Shanghai market.introduce的双语例句1. Now is not the time to introduce new routines.现在不是引入新的日常事务的时候。
Unit4 单元整体教学设计-高中英语人教版(2019)选择性必修第二册
Part 4: Teaching design：课时安排：小单元一
课时
第 1 课时
第 2 课时
内容
Opening Page Reading and Thinking（1）
课 型
学习目标
与主题相关的表达（单词+词块）
语法结构-ed/-ing
1. locate details about the rail
journey by skimming and
scanning the passage;
2. find discourse markers and
读思
understand them;
• structure features of journey
what, who, when, where, how, time
order
Part 4: Teaching design：单元学习目标
长途旅行贴近学生的生活。通过多模态语篇的学习，学生能够： 1. 获取、梳理、整合长途旅行主题相关的信息。 2. 巩固提高听、说、读、写技能。 3. 观察文本，辨别现在分词和过去分词，理解其功能和意义，并在
looking,
passing,
them to make a dialogue.
seen, amazed, rolling, confirming
Part 4: Teaching design：课时安排：小单元二
课时 内容
第 3 课时
Listening and Talking
语篇
Talk about scenery and culture along a journey
introduce的短语有哪些意思
introduce的短语有哪些意思introduce表示提出; 介绍; 引进的意思，能和introduce搭配成短语的词汇有哪些你知道吗，接下来店铺就为大家整理了introduce的短语搭配，希望对你有帮助哦!introduce的短语introduce into(v.+prep.)引进; 插入 put sb/sth inside sth or bring sb/sth into sthHe introduced the guest into the room.他把客人引进屋。
She introduced me into the lobby.她把我引进休息室。
introduce to(v.+prep.)把…介绍给; 使…了解 make known to or familiar with (sb else) 〔说明〕 introduce to通常不用于进行体。
I introduced John to Mary.我把约翰介绍给了玛丽。
Let me introduce you to my friend Nancy.让我把你介绍给我的朋友南希。
introduce的英英解释v.1. cause to come to know personally2. bring something new to an environment3. introduce4. bring in a new person or object into a familiar environment5. bring in or establish in a new place or environment6. put or introduce into something7. bring before the public for the first time, as of an actor, song, etc.8. put before (a body)9. furnish with a preface or introduction10. be a precursor ofintroduce的网络释义introduce采用，引进; 采用; 引进; 介绍，引见;to introduce介绍;introduce yourself介绍你自己：; 自我介绍; 新手报到;Introduce Me隆重介绍;introduce remarks提出意见;introduce的短语例句1. Britain did not introduce compulsory primary education until 1880.直到1880年，英国才开始实行初等义务教育。
introduce的用法和例句
introduce的用法和例句Introduce是一个动词，表示介绍、引入或提出某人或某事物。
它可以用于各种场合，包括社交、学术、商务等。
下面是一些关于introduce的用法和例句。
1. 社交场合：- Let me introduce you to my friend, Sarah. (让我介绍一下我的朋友，莎拉。
) - May I introduce myself? I'm John. (我可以自我介绍一下吗？我叫约翰。
) - Allow me to introduce my wife, Emily. (请允许我介绍一下我的妻子，艾米莉。
)2. 学术场合：- The professor will introduce the topic of the lecture. (教授将介绍讲座的主题。
)- The speaker will introduce the concept of quantum physics. (演讲者将介绍量子物理学的概念。
)- The textbook introduces the basic principles of chemistry. (这本教科书介绍了化学的基本原理。
)3. 商务场合：- I would like to introduce our new product line. (我想介绍一下我们的新产品系列。
)- The CEO will introduce the company's strategic plan. (首席执行官将介绍公司的战略计划。
)- We need to introduce our brand to a wider audience. (我们需要向更广泛的观众介绍我们的品牌。
)4. 提出观点或建议：- I would like to introduce the idea of implementing a recycling program. (我想提出实施回收计划的想法。
大雁塔英文解说词大雁塔英文导游词
大雁塔英文解说词大雁塔英文导游词大雁塔位于南郊大慈恩寺内，是全国著名的古代建筑，被视为古都西安的象征。
相传是唐僧从印度取经回来后，专门从事译经和藏经之处。
下面是店铺为大家整理的大雁塔英文解说词，希望可以帮助到你。
大雁塔英文解说词【一】Welcome to here, let me to introduce for everybody!"See China in five hundred, please come to Beijing, want to see China in five thousand, please go to xi 'an", see this you should know the history of the xi 'an long, xi 'an was the capital of 13 dynasties, is also one of the seven ancient capitals in China, together with Athens, Cairo, Rome more is known as the "world's four major ancient civilization". Xian, called chang 'an.Around xian imperial mausoleum, palace ruins, ancient temple of acquainting and garden scenic spots, is a treasure trove of xi 'an became a history and culture, numerous cultural relics to reveal it once had the brilliant and deep rich historical and cultural charm. Is in such a city, in this you can feel the Chinese for thousands of years of vicissitudes of life change, and the development of the Chinese civilization and the greatest of the Chinese nation.In Beijing on January 14, 2011, the national 5 a-class tourist scenic spot of opening ceremony, the xi 'an qujiang wild goose pagoda? Datang furong garden scenic spot success promotion national 5 a grade scenic spot, become after the Terra Cotta Warriors, huaqing pool and runs in our province, the fourth national 5 a-class tourist scenic spot, is the first company in xi 'an city 5 a level scenic area, is the first regional, many attractions whole packaging promotion national 5 a grade scenic spot.Xi 'an qujiang wild goose pagoda? Datang lotus park scenic area is located in the core region of xi 'an qujiang newly developed area, with a total area of 3.8 square kilometers, is China's only journal theme scenic spots. There are tang changan xuan zang translated by land, day - the temple of Buddhism; Xi 'an landmarks, one thousand sites - wild goose pagoda; Architectural landscape, nature, save big tang temple Ursa major temple tang big temple ruins park base sites; China's first comprehensive display of tang style park - datang furong garden.In the tang dynasty QuJiangChi site for dating, followed the open cultural experience of landscape pattern of the park - park QuJiangChi sites; After 1400 years of wind and rain of the tang dynasty city wall ruins, restore reproduce the character of the tang dynasty and the tang dynasty as the theme of the artistic conception of tang dynasty city wall ruins park; There is Asia's largest matrix water dance music square, leisure culture of great wild goose pagoda scenic area, dazzle beautiful tang Yin and datang city that never sleeps.Cultural and historical resources of the scenic spot, beautiful scenery and pleasant environment, everywhere embodies the concept of environmental protection and humanistic care, has become a new card in xian city, the ancient capital tourism new brand. Visitors enter the scenic area, every footprint walk on site, every journey to complete the dialogue with history.大雁塔英文解说词【二】Yong hui in the tang dynasty three years (AD 652), xuan zang wizard for sacrifice from India to Buddha, andother and classic Sanskrit, in temple west DaYuan 2-foot-tall tower built a five layer. Contrary to baoji famen temple tower by adding, wild goose pagoda is a temple built tower. During wu zetian changanreconstruction. Then after a lot of dressing. Wild goose pagoda is the famous tourist attraction in the tang dynasty, and therefore have a lot of literati, words, title of the Ming and qing dynasty which alone there are more than two hundred.Big wild goose pagoda in the temple is the tang dynasty monk xuan zang specializing in translation and the scriptures. Buddhist sutras introduced from tianzhu master xuan zang, once conducted temple in the temple service, with "fear generation who, after the loss, and difficult to fire" and make appropriate arrangements via like sarira, citing is outside a temple was built stone tower a, hence march Tang Yonghui three years (AD 652) attached to the chart to write.The emperor tang planning FuTu total 45 zhangs by xuan zang, with enormous project to achievement, and unwilling to mage toil, citing court grant funding 2-foot-tall tower built in the temple west yuan five layer. Wild goose pagoda, this tower due later in changan jianfu temple built a small wild goose pagoda, the temple tower was called wild goose pagoda, jianfu temple tower was called the small wild goose pagoda, has spread so far.Imitation of the western regions of great wild goose pagoda Su slope shape, wall brick surface soil core, not climbing, each layer sarira. Master xuan zang personally presided over a tower, built in two years. For brick topsoil heart, wind and rain erosion, more than 50 years after the tower gradually collapse.Wu zetian changan years (AD 701-701), the queen Wu zetian and nobility, give money to build on the site, for seven new layer, the blue brick flies in the tower (another story, 704 AD as of great wild goose pagoda, tower increased to 10 layers. In 931 AD, when the later tang dynasty five dynasties period to rebuilding, wild goose pagoda to seven layers). After tang dynasty, templetemple by repeated warfare, the house burned down, only the wild goose pagoda alone.In 931 AD (five generations of the later tang dynasty changxing two years) repair again for wild goose pagoda. Later in a large earthquake happened in xi 'an region, the wild goose pagoda tower fell, the tower shatter. (the original tower 11 floors) said "the second tablet" quiet st.大雁塔英文解说词【三】As the symbol of the old-line Xian, Big Wild Goose Pagoda is a well-preserved ancient building and a holy place for Buddhists. It is located in the southern suburb of Xian City, about 4 kilometers (2.49 miles) from the downtown of the city. Standing in the Da Ci'en Temple complex, it attracts numerous visitors for its fame in the Buddhist religion, its si-mp-le but appealing style of construction, and its new square in front of the temple.It is rated as a National Key Cultural Relic Preserve as well as an AAAA Tourist Attraction. This attraction can be divided into three parts: the Big Wild Goose Pagoda, the Da Ci'en Temple, and the North Square of Big Wild Goose Pagoda.Big Wild Goose PagodaOriginally built in 652 during the reign of Emperor Gaozong of the Tang Dynasty (618-907), it functioned to collect Buddhist materials that were taken from India by the hierarch Xuanzang.Xuanzang started off from Chang'an (the ancient Xian), along the Silk Road and through deserts, finally arriving in India, the cradle of Buddhism. Enduring 17 years and traversing 100 countries, he obtained Buddha figures, 657 kinds of sutras, and several Buddha relics. Having gotten the permission of Emperor Gaozong (628-683), Xuanzang, as the first abbot of Da Ci'en Temple, supervised the building of a pagoda inside it.With the support of royalty, he asked 50 hierarchs into the temple to translate Sanskrit in sutras into Chinese, totaling 1,335 volumes, which heralded a new era in the history of translation. Based on the journey to India, he also wrote a book entitled 'Pilgrimage to the West' in the Tang Dynasty, to which scholars attached great importance.First built to a height of 60 meters (197 feet) with five stories, it is now 64.5 meters (211.6 feet) high with an additional two stories. It was said that after that addition came the saying-'Saving a life exceeds building a seven-storied pagoda'. Externally it looks like a square cone, si-mp-le but grand and it is a masterpiece of Buddhist construction. Built of brick, its structure is very firm.Inside the pagoda, stairs twist up so that visitors can climb and overlook the panorama of Xian City from the arch-shaped doors on four sides of each storey. On the walls are engraved fine statues of Buddha by the renowned artist Yan Liben of the Tang Dynasty. Steles by noted calligraphers also grace the pagoda. As for the reason why it is called Big Wild Goose Pagoda, there is a legend. According to ancient stories of Buddhists, there were two branches, for one of which eating meat was not a taboo. One day, they couldn't find meat to buy.Upon seeing a group of big wild geese flying by, a monk said to himself: 'Today we have no meat. I hope the merciful Bodhisattva will give us some.' At that very moment, the leading wild goose broke its wings and fell to the ground. All the monks were startled and believed that Bodhisattva showed his spirit to order them to be more pious. They established a pagoda where the wild goose fell and stopped eating meat. Hence it got the name 'Big Wild Goose Pagoda'.Da Ci'en Temple Da Ci'en Temple is the home of Big Wild Goose Pagoda. In 648, to commemorate the dead virtuous queen, royalty ordered the building of a temple named 'Ci'en' (Mercy and Kindness), for which the status and scale far exceeded all others. Today, with an area of 32,314 square meters (38,648.5 square yards), one seventh of the original area, it still retains its grandeur.Before the temple, there stands a statue of hierarch Xuanzang, the meritorious hierarch. Walking on and acroa small bridge, visitors will see the gates of the temple. With guarding lions, the temple seems stately for lions were said to function as talismans.Entering the temple you will see two buildings-Bell Tower in the east and Drum Tower in the west. Inside the Bell T ower hangs an iron bell 15 tons (14.76 grotons) in weight. It was molded in 1548 in the Ming Dynasty (1368-1644). Along the central axis are arranged the Hall of Mahavira, Sermon Hall, Big Wild Goose Pagoda, and the Hall of Xuanzang Sanzang. In the Hall of Mahavira are three carved statues of Sakyamuni, and 18 arhats as well as Xuanzang. The Sermon Hall is where Buddhist disciples would listen to a sermon.A bronze statue of Amitabha is dedicated and a Buddha statue is collected by Xuanzang as oblation. The Hall of Xuanzang Sanzang is north of Big Wild Goose Pagoda. In this hall are Xuanzang's relic and a bronze statue of a seated Xuanzang. The inner wall is chiseled with murals depicting this hierarch's story. Renowned as the contemporary Dunhuang Buddhist storehouse praised by UNESCO, it is the biggest memorial of Xuanzang.。
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过孔（via）是多层PCB的重要组成部分之一，钻孔的费用通常占PCB制板费用的30%到40%。
简单的说来，PCB上的每一个孔都可以称之为过孔。
从作用上看，过孔可以分成两类：
一是用作各层间的电气连接；
二是用作器件的固定或定位。
如果从工艺制程上来说，这些过孔一般又分为三类，即盲孔(blind via)、埋孔(buried via)和通孔(through via)。
盲孔位于印刷线路板的顶层和底层表面，具有一定深度，用于表层线路和下面的内层线路的连接，孔的深度通常不超过一定的比率(孔径)。
埋孔是指位于印刷线路板内层的连接孔，它不会延伸到线路板的表面。
上述两类孔都位于线路板的内层，层压前利用通孔成型工艺完成，在过孔形成过程中可能还会重叠做好几个内层。
第三种称为通孔，这种孔穿过整个线路板，可用于实现内部互连或作为元件的安装定位孔。
由于通孔在工艺上更易于实现，成本较低，所以绝大部分印刷电路板均使用它，而不用另外两种过孔。
以下所说的过孔，没有特殊说明的，均作为通孔考虑。
从设计的角度来看，一个过孔主要由两个部分组成，一是中间的钻孔（drill h ole）,二是钻孔周围的焊盘区，见下图。
这两部分的尺寸大小决定了过孔的大小。
很显然，在高速,高密度的PCB设计时，设计者总是希望过孔越小越好，这样板上可以留有更多的布线空间，此外，过孔越小，其自身的寄生电容也越小，更适合用于高速电路。
但孔尺寸的减小同时带来
了成本的增加，而且过孔的尺寸不可能无限制的减小，它受到钻孔(drill)和电镀（plating）等工艺技术的限制：孔越小，钻孔需花费的时间越长，也越容易偏离中心位置；且当孔的深度超过钻孔直径的6倍时，就无法保证孔壁能均匀镀铜。
比如，现在正常的一块6层PCB板的厚度（通孔深度）为50Mil左右，所以PCB厂家能提供的钻孔直径最小只能达到8Mil。
二、过孔的寄生电容
过孔本身存在着对地的寄生电容，如果已知过孔在铺地层上的隔离孔直径为D2,过孔焊盘的直径为D1,PCB板的厚度为T,板基材介电常数为ε,则过孔的寄生电容大小近似于：C=1.41εTD1/(D2-D1)
过孔的寄生电容会给电路造成的主要影响是延长了信号的上升时间，降低了电路的速度。
举例来说，对于一块厚度为50Mil的PCB板，如果使用内径为10Mi l，焊盘直径为20Mil的过孔，焊盘与地铺铜区的距离为32Mil,则我们可以通过上面的公式近似算出过孔的寄生电容大致是：C=1.41x4.4x0.050x0.020/(0.032 -0.020)=0.517pF，这部分电容引起的上升时间变化量
为：T10-90=2.2C(Z0/2)=2.2x0.517x(55/2)=31.28ps 。
从这些数值可以看出，尽管单个过孔的寄生电容引起的上升延变缓的效用不是很明显，但是如果走线中多次使用过孔进行层间的切换，设计者还是要慎重考虑的。
三、过孔的寄生电感
同样，过孔存在寄生电容的同时也存在着寄生电感，在高速数字电路的设计中，过孔的寄生电感带来的危害往往大于寄生电容的影响。
它的寄生串联电感会削弱旁路电容的贡献，减弱整个电源系统的滤波效用。
我们可以用下面的公式来简单地计算一个过孔近似的寄生电感：L=5.08h[ln(4h/d)+1]其中L指过孔的电感，h是过孔的长度，d是中心钻孔的直径。
从式中可以看出，过孔的直径对电感的影响较小，而对电感影响最大的是过孔的长度。
仍然采用上面的例子，可以计算出过孔的电感为：L=5.08x0.050[ln(4x0.050/0.010)+1]=1.015nH 。
如果信号的上升时间是1ns，那么其等效阻抗大小为：XL=πL/T10-90=3.19Ω。
这样的阻抗在有高频电流的通过已经不能够被忽略，特别要注意，旁路电容在连接电源层和地层的时候需要通过两个过孔，这样过孔的寄生电感就会成倍增加。
四、高速PCB中的过孔设计
通过上面对过孔寄生特性的分析，我们可以看到，在高速PCB设计中，看似简单的过孔往往也会给电路的设计带来很大的负面效应。
为了减小过孔的寄生效应带来的不利影响，在设计中可以尽量做到：
1、从成本和信号质量两方面考虑，选择合理尺寸的过孔大小。
比如对6-10层的内存模块PCB设计来说，选用10/20Mil（钻孔/焊盘）的过孔较好，对于一些高密度的小尺寸的板子，也可以尝试使用8/18Mil的过孔。
目前技术条件下，很难使用更小尺寸的过孔了。
对于电源或地线的过孔则可以考虑使用较大尺寸，以减小阻抗。
2、上面讨论的两个公式可以得出，使用较薄的PCB板有利于减小过孔的两种寄生参数。
3、PCB板上的信号走线尽量不换层，也就是说尽量不要使用不必要的过孔。
4、电源和地的管脚要就近打过孔，过孔和管脚之间的引线越短越好，因为它们会
导致电感的增加。
同时电源和地的引线要尽可能粗，以减少阻抗。
5、在信号换层的过孔附近放置一些接地的过孔，以便为信号提供最近的回路。
甚至可以在PCB板上大量放置一些多余的接地过孔。
当然，在设计时还需要灵活多变。
前面讨论的过孔模型是每层均有焊盘的情况，也有的时候，我们可以将某些层的焊盘减小甚至去掉。
特别是在过孔密度非常大的情况下，可能会导致在铺铜层形成一个隔断回路的断槽，解决这样的问
题除了移动过孔的位置，我们还可以考虑将过孔在该铺铜层的焊盘尺寸减小。