中考专项训练

合集下载

中考语文记叙文阅读专题训练专项训练100(附答案)含解析

中考语文记叙文阅读专题训练专项训练100(附答案)含解析

中考语文记叙文阅读专题训练专项训练100(附答案)含解析一、中考语文记叙文阅读专题训练1.阅读下文,回答问题。

在心头赵汀生我小学四年级的语文老师也是我们班主任,姓曹,四五十岁的样子,戴着副玳瑁眼镜,镜片形似鸡蛋,厚如陶瓷碗底,像有圈圈螺纹。

语文课若有偷看小人书做小动作的,不论在哪个角落,他总是先扶扶眼镜,注视片刻,轻咳几下,然后用教鞭敲着讲台,说:“这怎么行呢?”当时同学们大多有些怵他,背地里叫他“眼镜”。

我们班的自习课原本和其他班一样,没有老师,大家在教室里随意走动,交头接耳,很是自在。

后来“眼镜”将大半自习课用于自习语文,他总是坐在讲台旁批改作业,谁也不敢“轻举妄动”,教室里鸦雀无声,只有沙沙沙写字的声音。

一天下午,最后一节课是自习课,下课铃响后,曹老师从讲台旁站起来,扶了扶眼镜,压低嗓门说:“放学后我带同学们去游泳,会游泳的请举手。

”我们这个小山城溪河交错,深潭也很多,几乎每年都有学生在游泳时溺亡,老师和家长通常不许孩子去游泳。

但炎炎夏日里,游泳对孩子们,尤其小男孩,是极大的诱惑,常有人偷偷下河。

此刻,平日里颇为严厉古板的“眼镜”,竟要带大家去游泳,幸福来得实在有点意外。

教室里一下子喧嚣起来,那些预备下课后冲出去抢占乒乓球桌的男生,赶紧将攥在手里的自制光板球拍塞回书包。

选择去游泳的最后只有男生。

到得一处宽阔的河滩,曹老师叫我们站成一排,报了两遍数才让下水。

我与同学们打了一阵水战,又连扎了几个猛子浮出水面,见不远处河面上有两点亮光,抹去脸上的水珠一看,原来是曹老师正面对着我们站在水中,眼镜反射着太阳光,一闪一闪的。

我游到曹老师跟前,请他和我们一起去游泳,他摇了摇手说:“我还是不游吧,万一眼镜掉进河里,就什么都看不清了。

”我说这样泡在水里不动太冷了,他扶了扶眼镜:“没关系。

我眼睛不好使,你去告诉大家,不要离我太远,这样才看得见你们。

”太阳落下山去,渐渐起了风,柳枝拂着水面窸窣作响。

此时刚过端午节,河水还有些凉,水中的我们已感到了微微寒意,陆续往河岸游去。

2023年中考语文广州专项训练:积累运用专项训练(含答案)

2023年中考语文广州专项训练:积累运用专项训练(含答案)

2023年中考语文广州专项训练-积累运用专项训练说明:满分120分。

训练用时90分钟。

第一组1.默写古诗文。

(共10分。

答对一句得1分,满分不超过10分)(1)欲济无舟楫,______________________。

坐观垂钓者,______________________。

(孟浩然《望洞庭湖赠张丞相》)(2)____________________,影入平羌江水流。

夜发清溪向三峡,____________________。

(李白《峨眉山月歌》)(3)冰霜正惨凄,终岁常端正。

______________________?______________________。

[刘桢《赠从弟》(其二)](4)李白《行路难》(其一)中以“______________________,______________________”两句诗来比喻人生道路的艰难险阻和失意无奈。

(5)及鲁肃过寻阳,与蒙论议,大惊曰:“____________________,_____________!”(《孙权劝学》)(6)前不见古人,后不见来者。

______________________,______________________!(陈子昂《登幽州台歌》)2.根据拼音写出相应的词语。

(4分)(1)每每想起小时候在村里上灯学,要挑了灯笼走去挑了灯笼走回的事,便深深感到chàng wǎng()。

(2)无论一生遭受多少kùn è()欺诈,请依然相信人类的光明大于暗影。

(3)以上是从各种艺术中xìn shǒu niān lái()的几个实例。

(4)我认识奥本海默时他已四十多岁了,已经是fù rú jiē zhī()的人物了。

3.下列句子中加点的词语使用不恰当的一项是()(3分)A.没有成功的经验可以借鉴,没有现成的教科书,一切靠自己摸索。

B.他坚持传统文化与地方特色相结合,恪守工匠精神,把平凡的工作做得有声有色。

中考选词填空专项训练(含答案)

中考选词填空专项训练(含答案)

选词填空专项训练1、依次填入下列句子横线的词语,恰当的一项是( )①舞台上台湾女艺术家的演奏动听,观众在这经典乐曲里如痴如醉。

②22-在进行旅游开发论证的千岛湖水下古城,其历史可以到一千年以前。

③只有拥有了广博的阅历、丰富的语汇,我们创作作品才有可能。

A.优雅追溯一气呵成 B.优雅追述一鼓作气C.幽雅追述一气呵成 D.幽雅追溯一鼓作气2、根据下面语境,选择恰当的词语,将序号填在空格处。

我们曾随范仲淹登楼(1)浩淼的洞庭湖,感受它的气象万千;我们曾随郭沫若静静(2)灿烂的星空,领略天街的美妙神奇;我们也曾随宗璞驻足(3)繁盛的紫藤萝,感悟朴索的人生哲理。

A.凝望 B.眺望 C.仰望3、读下面这段文字,为空格处选择合适的词语,将其序号填在横线上。

在这个精彩纷呈的年代,我们要拥有一双智慧的眼睛。

我们登上山巅,⑴旖旎壮丽的山川,留存美丽的风景;我们细数历史,⑵名垂千古的先贤,接受灵魂的洗礼;我们畅想前景,⑶灿烂美好的未来,获取希望的动力。

A.展望 B.眺望 C.仰望4、根据下面语境,选择合适的词语填写在相应的横线上。

行走在诗意的江南,醇厚的文化味儿让你陶醉。

迷人的田野着四千年蚕桑的浓厚气息,宁静的乡村着耕读传家的人文精神,热闹的古镇着中华商业文明的辉煌。

在这里,自然与文化交融,传统与现代互动,处处展现出水乡独特的神韵和魅力!A.隐含B.彰显C.散发5、根据下面语境,选择恰当的词语,将序号填在横线上。

我梦想漫步在钱塘江畔,在潮起潮落中,感受“震撼激射,吞天沃日”的⑴;我梦想徜徉在滕王阁下,在落暮余辉里,想象“千里逢迎,高朋满座”的⑵;我梦想登临泰山之巅,在红日喷薄时,欣赏“造化钟神秀,阴阳割昏晓”的⑶。

A.壮阔B.壮丽C.壮观6、根据语境,依次填写词语最恰当的一项是( )①在一片中,我伏在岩石上,恐惧和疲乏使我全身麻木,不能动弹。

②最使我吃惊的是,后边几排一向空着的板凳上坐着好些镇上的人,他们也跟我们一样。

中考物理考点复习专项训练-功和机械能

中考物理考点复习专项训练-功和机械能

人教版中考物理考点复习专项训练-功和机械能姓名:__________ 班级:__________考号:__________一、单选题(共10题)1.(2分)(2023八下·顺义期中)在国际单位制中,功的国际单位是()A.焦耳B.千克C.秒D.牛顿2.(2分)(2023·太和模拟)我国航天事业取得了辉煌成绩,神舟十五号航天员出舱活动的情景如图所示。

当航天员站立在空间站外跟随空间站围绕地球从近地点向远地点运动的过程中,航天员的()A.动能不变B.重力势能增大C.机械能增大D.动能、重力势能均不变3.(2分)(2023九下·天门月考)如图所示是蹦床运动员正在比赛中的情景,运动员从最高点竖直落到蹦床上直至最低点的过程中(不计空气阻力),下列说法正确的是()A.在此过程中运动员的重力势能一直减小,动能一直增大B.最高点时,运动员速度为0,受平衡力的作用C.在运动员与蹦床刚要接触时,运动员具有的动能最大D.在此过程中,运动员的机械能先不变再减小4.(2分)(2023·宾阳模拟)如图所示,载有3名航天员的神舟十四号载人飞船进入太空。

载人飞船加速升空过程中以下说法正确的是()A.飞船的动能增大,机械能不变B.飞船的重力势能增大,机械能不变C.飞船的重力势能转化为动能,重力势能减小D.燃料燃烧后通过做功,把内能转化为飞船的机械能5.(2分)(2023九上·南县期末)如图所示,小球以速度v从A沿弯曲轨道滑下,并最终刚好到达等高的C点,下列说法中正确的是( )A.因为最终到达了与A等高的C点,所以小球机械能守恒B.小球在B点的机械能最大C.小球从B到C的过程只是动能转化为重力势能D.小球从A到C的整个过程中动能的变化量等于克服摩擦力做功6.(2分)(2023·天长模拟)乒乓球发球机在同一高度以相同的初速度朝不同方向分别发出a、b、c三个球,若不计空气阻力,则落到水平桌面时三者的速度大小关系是()A.v a>v b>v c B.v b>v c>v aC.v a>v c>v b D.v a=v b=v c7.(2分)(2023八下·长春期中)冬奥会期间,奥运村部餐饮处的智能送菜机器人大放异彩。

中考复习现在完成时专项练习题(含部分答案)

中考复习现在完成时专项练习题(含部分答案)

中考现在完成时专项训练1.—Dad, I ________ the station for minutes, but nobody came to meet me.—Don’t worry. I’ll go to meet you soon.A. arrived atB. have been atC. will reachD. have arrived at2.—______ you ever ______ Dali? —Never. But I am going there this vacation.A. Do; go toB. Have; been toC. Have; gone toD. Will; go to3.My aunt is a writer. She ____ more than ten books since 1980.A. writesB. wroteC. has writtenD. will write4.Echo _____ for half a month. She’ll come hack in two months.A. left B leave C. has left D. has been away5.The Smiths came to Shanghai in 2008, they there for three years since then.A. liveB. livedC. have livedD. will live6.— Have you ever been to Nanning? — Yes, _______ .A. I wasB. I doC. I amD. I have7.I my homework. I guess I can't join you.A. don't finishB. didn't finishC. haven't finishedD. won't finish8.—Excuse me, where is Mr. Brown's office?—Sorry, I don't know. I _____ here for only a few days.A. workB. workedC. have workedD. will work9.—Where is Bob? —He ______to Harbin for a meeting.A. wentB. has beenC. has goneD. goes10.— Are you going to the bank, Laura? —No, I ______ to the bank already.A. have beenB. have goneC. am goingD. had been11.---Oh, you are here. I’m looking for you all the morning. ?----To the library.A. Where have you goneB. Where will you goC. Where are you goingD. Where have you been?12.So far this year, many new houses ____ in Wenchuan with the help of the government.A. buildB. are builtC. will buildD. have been built13.My grandmother ______ a lot of changes in Tianjin since she came here.A. seesB. can seeC. will seeD. has seen14.I many new friends since I came here.A. makeB. madeC. will makeD. have made15.Mrs. Weng came back from France in 2010. She _____ there for four years.A. worksB. workedC. has workedD. will work16."Where's your brother, Jane?""He's not in Guiyang these days. He________ Beijing.”A. has gone toB. has been toC. had been toD. had gone to17.She _______ this book for nearly three weeks.A. has borrowedB. has lentC. has boughtD. has kept18.They _____ England and they will be back next week.A. have gone toB. have been toC. have gone inD. has been on19.He_______ in this city since his family moved to Nanchong.A. liveB. livedC. has lived20.Some students in Shanghai e-bags for several months.A. haveB. have hadC. hadD. will have21.—Is Mr. Smith still in Shanghai?—Yes, he ______ there for two months.A. has beenB. has goneC. has been toD. has gone to22.My brother and I _____ in Yinchuan since 1997.A. had livedB. have livedC. liveD. will live23.My pen pal said he would write to me, but I ___ any letters from him so far.A. won’t receiveB. haven’t receivedC. hadn’t receivedD. didn’t receive24.Our country ______the sixth population census(人口普查) already.A. finishedB. has finishedC. will finishD. finishes25.Thomas ______ the army for two years, so he misses his mother very much.A. has joinedB. has taken part inC. has been in26.—How well do you know the Opera House?—I know the place very well. I ____ Sydney many times.A. have been inB. have been toC. have gone toD. have arrived in27.---How clean the bedroom is!---Yes, I am sure that someone it.A. cleansB. cleanedC. has cleanedD. had cleaned28.Where is Ben? —He ____ to the teachers’ office. He will be back soon.A. goB. has goneC. has beenD. goes29.I ______my hometown for a long time, I really miss it!A. leftB. went away fromC. have leftD. have been away from30.—Will you please go to see the movie Guanyinshan with me?—No, I won’t. I ______ already.A. sawB. have seenC. seeD. will see31.-Where is John? -He ______ the science lab.A. has gone toB. has been toC. went to32.How do you like your English teacher?— He is great. We friends since three years ago.A. wereB. have madeC. have beenD. have become33.—Hi, guys. Where are you heading now?—Home. We _________all our money, so we have to walk home now.A. spendB. spentC. have spentD. are spending34.--_____ you _____ the movie Gongfu Panda II ?—Not yet. I'll see it this Sunday.A. Did, seeB. Do, seeC. Have, seen35.British Prince William(威廉王子) and Kate _____ for nearly two months.A. marriedB. have marriedC. have been marriedD. have got married36.Jim _________ in Zhuzhou since he finished his college.A. worksB. is workingC. has worked37.—May I speak to Lin Tao?—Sorry, he is not in. He ______ to Changsha.A. has beenB. has goneC. went38.Great changes _________ in Tongren in the past five years.A. have happenedB. have taken placeC. have been happenedD. have been taken place39.He promised to pick me up at the school gate. However, he __ yet.A. didn't arriveB. doesn't arriveC. isn't arriving D hasn't arrived40.You are too late. The film ______ since half an hour ago.A. has begunB. has been onC. began41.---- Why won’t you go to the movie with me, Gina?--- Because I it twice.A. seeB. have seenC. sawD. will see42.-Where's your father, Tom? -He__ to Changsha.A. goesB. wentC. has gone43.Where is my sister, mum? - She ______ to the library. She will be back soon.A. has beenB. is goingC. has goneD. will go44.—May I speak to Mary?—Sorry, she isn’t in. She to Japan and will come back in two weeks.A. has beenB. has goneC. is going45.—Are Li Yan and Wang Mei still living in Pingba? —No, they ____ to Shanghai.A. had movedB. movedC. will moveD. have moved46.Mr. Fan ___ this watch in 2005. He ____ it for 6 years.A .bought, has had B. bought, has C. has bought, has had D. has bought, had47.Mr. White came to our school in 2008, and since then he us English.A. teachesB. taughtC. has taughtD. will teach48.—China develops so fast. —That’s true. It ______ a lot already.A. changesB. changedC. will changeD. has changednmon ______ here for almost ten years and he has many Chinese friends.A. has beenB. leftC. has comeD. came50.—Have you ever visited Germany? —____________. But I expect to go there again.A. PerhapsB. No, I haven’tC. I don’t knowD. Yes, I have51.—May I speak to Miss Wang? —Sorry. She isn’t in. She __________ to Hong Kong.A. has beenB. has goneC. goesD. went52.Sam came to Baihai in 2002. He __________ here for nine years.A. livesB. was livingC. has livedD. will live53.He _____in Xinxiang for five years when I heard his news.A. has livedB. had livedC. is livingD. has been lived54.Our school is having a sports meeting. Someone _____ here already.A. arrivedB. have arrivedC. has arrived55.The meeting by the time I got there yesterday.A. was onB. has been onC. had begunD. has begun56.By the end of last month, I _____ all the CDs of Justin Bieber.A. collectB. collectedC. have collectedD. had collected57.By the time I got to the cinema, the movie _______ for ten minutes.A. had begunB. had been onC. has startedD. has been on58.Jim isn’t in the classroom. Where is he?He _____ to the teacher’s office.A. will goB. has goneC. had goneD. is going59.His brother has been to Stone Forest twice______ he came to Yunnan.A. afterB. beforeC. sinceD. for60.Tom ______the CD player for two weeks.A. has lentB. has borrowedC. has boughtD. has had(二)1.Both his parents look sad. Maybe they _________what's happened to him.A. knewB. have knownC. must know D.will know2.He has_______ been to Shanghai, has he ?A.already B. never C. ever D. still3.Have you met Mr. Li ______?A.just B. ago C. before D. a moment ago4.The famous writer _____ one new book in the past two year .A. is writingB. was writingC. wrote D.has written5.—Our country ______ a lot so far. —Yes. I hope it will be even ______ .A. has changed; wellB. changed; goodC. has changed; better D.changed; better6.Zhao Lan ______already ______in this school for two years .A. was; studyingB. will; studyC. has; studied D. are; studying7.We ______ Xiao Li since she was a little girl.A. knowB. had knownC. have known D.knew8.Harry Potter is a very nice film. I_______ it twice.A.will see B. have seen C. saw D.see9.—These farmers have been to the United States. —Really? When _____ there?A. will they goB. did they goC. do they go D.have they gone10.—______ you ___ your homework yet? —Yes. I _____ it a moment ago .A.Did; do; finished B. Have; done; finishedC. Have; done; have finishedD. will; do; finish11.His father ______ the Party since 1978 .A.joined B. has joined C. was in D.has been in12.—Do you know him well? — Sure .We _________ friends since ten years ago.A.were B. have been C. have become D. have made13.—How long have you ____ here ? —About two months .A.been B. gone C. come D.arrived14.Hurry up! The play __________ for ten minutes .A.has begun B. had begun C. has been on D.began15.It _____ ten years since he left the army.A.is B. has C. will D.was16.Miss Green isn't in the office. she_______ to the library .A.has gone B. went C. will go D.has been17.My parents ______ Shandong for ten years.A.have been in B. have been to C. have gone to D. have been18.The students have cleaned the classroom, ?A. so theyB. don’t theyC. have theyD. haven’t they19.______has Mr. White been a member of Greener China since he to China?A. How soon, comesB. How often, gotC. How long, cameD. How far, arrived20.His uncle for more than 9 years.A. has come hereB. has started to workC. has lived thereD. has left the university21.We have been friends since ______.A. childrenB. five yearsC. five years agoD. five years before22.Mike ___________ the story book for a month.A. has boughtB. has hadC. have hadD. has borrowed23.You ______ that question three times.A. already askedB. have already askedC. already have askedD. asked already24.Those foreign friends left Guangzhou __________.A. since last weekB. a week agoC. for a weekD. since a week ago25.I _____ at this school for two years.A. am studyingB. studyC. studiedD. have studied26.They _________ in the city since last summer.A. liveB. didn’t liveC. have livedD. live27.Mrs. Wang has lived in California _________ 1992.A. sinceB. fromC. afterD. in28.Mr. Black _________ China since the summer of 1998.A. has been toB. has been inC. has come toD. came to29.Li Hong has ________ the army for 2 years.A. joinedB. be inC. been inD. joined in30.His father _______ for years.A. has diedB. has been deadC. diedD. dies31.Mary ________ to see the films because she __________ it twice.A.won’t go, sawB. didn’t go, has seenC. won’t go, has seenD. didn’t go, sees32.--- Would you like some more food? ----Thank you. I _______ enough.A. will haveB. have hadC. haveD. had33.______ you ______ England? Yes, it _____ a beautiful country.A. Will, gone to, wasB. Have, been to, isC. Had, been to, isD. Have, gone to, is34.---_____ you _____ to Beijing? ----No, I ____.I ____ there early next month.A. Have, been, haven’t, am goingB. Had, been, hadn’t, am goingC. Have, gone, haven’t, was goingD. Did, go, didn’t, was going35.--You sister ___ to London to study English. Is that true?--Yes, she ___ there for two months.A. has been, has beenB. will go, has goneC. gone, will beD. has gone, has been36.He has a computer of his own. He ____ it two days agoA. buysB. has hadC. boughtD. has bought37.—Where is Li Lei? —He ___ Shanghai.A. has gone toB. has been toC. went toD. goes to38.He _______ his homework and is now listening to music.A. finishesB. has finishedC. finishD. is finishing39.David _______ Shanghai for more than three months.A. came toB. has been toC. has been inD. has come to40.--- Is your father a Party member?--- Yes, he ____ the party three years ago. He _____ a Party member for three years.A. joined; has beenB. has joined; has beenC. was joined; isD. joined; was41.---What a nice bike! How long ____ you ____ it? ----Just five weeks.A. have; buyB. did; buyC. are; havingD. have; had42.I ______ this book for a week .I have to return it now.A. borrowedB. have borrowedC. keptD. have kept43.----______ your sister _______ in Green China for a long time?---Yes. She joined it five years ago.A. Has; beenB. Have; beenC. Has; joinedD. Have; joined44.---How long have you _______ from the USA? ----For three months.A. come backB. returnedC. go backD. been back45.I _____ this book for half a year.A. have boughtB. have hadC. boughtD. had46.The students are sorry to hear that famous singer _______ for a year.A. has leftB. has goneC. has been awayD. has gone away47.--- ______ you______ your homework yet? ---Yes, I _____ it just now.A. Did; do; finishedB. Have; done; finishedC. Have; done; have finishedD. Will; do; finish48.The sand storm weather ______ in Beijing several times this year.A. happenB. happenedC. has happenedD. have happened49.---How long have you been here? --- ____ last month.A.ForB. UntilC. BeforeD. Since50.He ____ a cold for three days.A. has caughtB. has hadC. has gotD. caught51.Jim Green ____ in China for two years.A. has comeB. has beenC. has arrivedD. came52.The film ____ for half an hour.A. has been onB. has begunC. hasn’t begunD. began53.—Where have you _______ these days?—I have to Beijing with my friends.A. been; goneB. been; beenC. gone; beenD. gone; gone54.How long have you _______ this book?A. boughtB. borrowedC. keptD. lent55.We have lived here _______ five years ago.A. whenB. sinceC. before D.after56.—I have watched the game.—When _____you _______ it?A. have; watchedB. do; watchC. did; watch D.will; watch57.—How do you like Beijing, Mr. Black?—Oh,I _______ such a beautiful city.A. don’t visitB. didn’t visitC. haven’t visited D.hadn’t visited58.Miss Brown _______ to the Great Wall twice.A. have beenB. has beenC. have goneD. has gone59.His brother has been to Stone Forest twice ______ he came to Yunnan.A. whenB. beforeC. sinceD. for60.His grandpa _______ for two years.A. was diedB. has been deadC. was deadD. has died61.—Have you ever_____ to Haikou?—Yes,I_____ there with my family last August.A. gone; wentB. been; wentC. been; went toD. been; was in62.His sister ______ her hometown for three years. She’ll return next year.A. leftB. has leftC. has been awayD. has been away from63.I ___ the dictionary to her yet.A. have givenB. haven’t givenC. will giveD. gave64.Tom is not here. He _____to Beijing for a holiday.A. has beenB. have beenC. have goneD. has gone65.How long have you _____the novel?A. keptB. borrowedC. lentD. given66.I'm sorry you've missed the train.It________10 minutes ago.A. leftB. has leftC. had leftD. has been left67.-Mum, may I go out and play basketball? - you ___________ your homework yet?A. Do, finishB. Are, finishingC. Did, finishD. Have, finished68.-Excuse me, no photos here! -Sorry, I ______________ the sign.A. don't seeB. didn't seeC. can't seeD. won't see69.No hurry! We can get to the bus station in time and we ___________ the early bus.A. don't missB. can missC. will missD. won't miss70.Our teacher, Miss Chen ____________ English on the radio the day before yesterday.A. teachesB. taughtC. will teachD. has taught71.Harry Potter is a very nice film. I ___________it twice.A. had seenB. can seeC. have seenD. see72.Jim has made many friends since he ____________to China.A. cameB. comesC. has comeD. will come73.----Lucy, you ________your ticket? ---Not yet.A. can, findB. have, foundC. has, foundD. do, find74.What _________we _________if our car breaks down broken on the way?A. do, doB. did, doC. are, doingD. shall, do75.We'll go for a walk if it ______________ tomorrow.A. will not rainB. rainsC. doesn't rainD. rainy76.Listen! Mary ____________in the next room.A. singsB. is singingC. sangD. sing77.China _________the WTO in 2001.A. joinedB. has joinedC. had joinedD. join78.--How long ____ you ____a fever? ---Ever since last night.A. have, gotB. have, hadC. have, caughtD. did, have79.---The rain came to a stop last night. The fields are still full of water now.---It _____ for nearly a week.A. has rainedB. had rainedC. would rainD. was raining80.--Sorry. I am late. ---It doesn’t matter. The meeting ______ for just several minutesA. has begunB. has startedC. has been onD. had been on81.---_____ you _____ your breakfast? ---Yes, I have.---When _____ you _____ it? ---Twenty minutes ago.A. Have; have; have; hadB. Did; have; did; haveC. Have; had; do; haveD. Have; had; did; have82.---_____ your homework yet? ---Not yet, I ________it.A. Have you done; am doingB. Did you do; didC. Did you do; am doingD. Have you done; did83.---Where_____ the recorder? I can't see it anywhere.---I _____ it right here half an hour ago. But now it is gone.A. did you put; have putB. have you put; putC. do you put; puttingD. did you put; have put84.Mr. Green _______ China for three years.A. has been toB. has come toC. has been inD. has arrived in85.My brother _____ since I came home.A has gone to bed B. has been asleep C has fallen asleep D. has been sleepy86.Has he read this book ______?A. everB. alreadyC. yetD. never87.The old man________ since 2000.A. diedB. has diedC. has been deadD. has dead88.He is late. The film has ______ for half an hour.A. begunB. beganC. openedD. been on89.How long will he _____ China?A. leaveB. be away fromC. leftD. stay90.--- “Where can I find Tack?” ----“ He ________ the post office.”A. has been toB. had been toC. has gone toD. had gone to91.Have you ever ______ the USA?A. been toB. gone toC. been inD. go to92.She ________ China since she _______.A. has been to, arrivesB. has been to, arrivedC. has been in , arrivedD. has gone to, arrived93.It _____ five years since we _____ last time.A. is ; have metB. has been; have metC. is; metD. was; have met94.---Have you finished your homework ? --- Yes, I _______ it last night.A. have finishedB. has finishedC. finishedD. is finishing95.Kate’s never seen Chinese films,____ ?A. hasn’t sheB. has sheC. isn’t sheD. is she96.-Ann has gone to Shanghai. -So ______her parents.A. hasB. hadC. didD. have97.-Mum, may I go out and play basketball? -_____you___ your homework yet?A. Do; finishB. Are; finishingC. Did; finishD. Have; finished98.-______ you ______anywhere before? -Yes, but I can’t remember where I______A. Did; surf; surfedB. Have; surfed; surfedC. Did; surf; have surfedD. Have; surfed; have surfed99.I______ a letter from him since he left.A. didn’t receiveB. haven’t gotC. didn’t haveD. haven’t heard100.-Have you ever______ Xi’an to see the Terra Cotta Warriors?-Yes, I have.A. went toB. gone toC. been inD. been to101.My parents ______ Shandong for ten years.A. have been inB. have been toC. have gone toD. have been 102.I ____my ticket so I ca n’t go to the concert.A. lostB. don’t loseC. have lostD. is coming二、用所给词的适当时态填空:1.He often ________(go) to school by bike .2._____you usually ________(get) up at seven in the morning ?3.I __________ (come) to Tianjin in 1994.4.His aunt ____________ (be) a actress ten years ago.5.I _______ already _________ ( finish ) my homework.6.She _____________ (do) her housework yet.7.He _______ (live) in Beijing for three years.8.They __ _____(be) in this school since eight years ago.9.He isn’t here. He ____________ (go) to Beijing.10.She ______ never ________ (be) there before.11.The teacher ______ just ________ ( finish ) teaching us.12._________ you ever ___________ ( taste ) dumplings .13.So far they _______ (learn)two thousand words.14.He said he _______________ ( never see )such an exciting match before.15.By the time we got there , the bus ________ already ________(go).16.She _____________ (live) here ever since she was ten.17.Both of them ________________ (be) in Hong Kong for ten days.18.Both of them ____________ (come) to Hong Kong ten days ago.19.Half an hour __________ (pass) since the train __________ (leave).20.Mary________(lose) her pen. _____ you _______(see) it recently?21._________ you _____ (find) your watch yet?22.---Are you thirsty? ---No I _________just _________ (have) some orange.23.We already _________ (return) the book.24.________ they already_______ (build) a school in the village?25.I _____________(not finish) my homework . Can you help me?26.My father _____ (read) the novel twice.27.I _________ (buy) a book just now.28.I _________ (lost ) my watch yesterday.29.My father ___________ (read) this book since yesterday.30.He ___________ (learn) about 5,000 English words since he_____ (go)to college.四、填空(一)用have / has been to / in, have gone to及go的各种形式填空。

初中中考语文对联专项训练练习和答案

初中中考语文对联专项训练练习和答案

初中中考语文对联专项训练练习和答案1.根据课文内容,将对偶句补充完整。

岳阳楼上范仲淹作文寄情,_______欧阳修_______。

2.运用对偶知识对出下联。

1上联:忆往昔沧桑岁月下联:____ ___2上联:品千古美文下联:___ ____3上联:____ _ 下联:花静鸟淡天4上联:风声雨声读书声,声声入耳下联:___________ _5上联:郭沫若向往光明勾画天上街市下联:陶渊明_______ _____6上联:海安花鼓,誉满神州下联:___________ _ 从下列提示中选出一个对象对出下联:品王佳酿、海林内衣、中洋河豚。

7下面是教师节某学生献给辛勤园丁的一副对联,请你拟写下联。

上联:无声润物三春雨下联:______________3.诸葛亮凭借才智,辅佐刘备争得了三国鼎立的局面,建立了盖世功业。

相传他曾推演兵法,聚石布成八阵图。

下面一副对联是杜甫对他的评价,清你补充完整。

上联:功盖三分国下联:名成_______4.徐特立先生曾经赠给青年人一副对联,请你补充完整。

仁联:有关家国书常读下联:______________5.楚汉战争时期由于萧何的推荐,韩信被拜为大将,也由于萧何的计谋,韩信又惨遭杀害。

韩信少时,常常挨饿,漂母怜而饭之才得以生存,而最后他又死于吕后之手。

请你用一副对联来概括韩信的一生。

6.林则徐赴广州查禁鸦片后被任命为两广总督,他在总督府写了一副对联以自勉,表示自己光明磊落的胸怀与刚正不阿、无私无畏的品格。

请你补出上联。

上联:______________ 下联:壁立千仞,无欲则刚。

7.杭州西湖边上岳飞墓前有秦桧等四人的铸铁跪像,人们借此来贬恶扬善。

当年秦桧等人谋害岳飞,为后人唾骂理所当然,但用来塑像的白铁则是无辜的。

请你据此完成下面的对联。

上联:青山有幸埋忠骨下联:______________8.《醉翁亭记》语言形式优美,尤其是对偶句充分体现了汉语的美感。

请以“欧刚修与百姓同乐”为上联,联系《岳阳楼记》一文,拟一个下联。

几何最值问题-2023年中考数学压轴题专项训练(全国通用)(解析版)

12023年中考数学压轴题专项训练1.几何最值问题一、压轴题速练1一、单选题1(2023·山东烟台·模拟预测)如图,在矩形ABCD 中,AB =8,AD =4,点E 是矩形ABCD 内部一动点,且∠BEC =90°,点P 是AB 边上一动点,连接PD 、PE ,则PD +PE 的最小值为()A.8 B.45 C.10 D.45-2【答案】A【分析】根据∠BEC =90°得到点的运动轨迹,利用“将军饮马”模型将PE 进行转化即可求解.【详解】解:如图,设点O 为BC 的中点,由题意可知,点E 在以BC 为直径的半圆O 上运动,作半圆O 关于AB 的对称图形(半圆O '),点E 的对称点为E 1,连接O 'E 1,则PE =PE 1,∴当点D 、P 、E 1、O '共线时,PD +PE 的值最小,最小值为DE 1的长,如图所示,在Rt △DCO '中,CD =8,CO '=6,∴DO '=82+62=10,又∵O 'E 1=2,∴DE 1=DO '-O 'E 1=8,即PD +PE 的最小值为8,故选:A .【点睛】本题考查线段和最短问题、轴对称的性质、勾股定理及圆周角定理,利用“将军饮马”模型将PE 进行转化时解题的关键.2(2023·安徽黄山·校考模拟预测)如图,在平面直角坐标系中,二次函数y =32x 2-32x -3的图象与x 轴交于点A ,C 两点,与y 轴交于点B ,对称轴与x 轴交于点D ,若P 为y 轴上的一个动点,连接PD ,则12PB +PD 的最小值为()2A.334B.32C.3D.543【答案】A【分析】作射线BA ,作PE ⊥BA 于E ,作DF ⊥BA 于F ,交y 轴于P ,可求得∠ABO =30°,从而得出PE =12PB ,进而得出PD +12PB =PD +EP ,进一步得出结果.【详解】解:如图,作射线BA ,作PE ⊥BA 于E ,作DF ⊥BA 于F ,交y 轴于P ,抛物线的对称轴为直线x =--322×32=12,∴OD =12,当x =0时,y =-3,∴OB =3,当y =0时,32x 2-32x -3=0,∴x 1=-1,x 2=2,∴A (-1,0),∴OA =1,∵tan ∠ABO =OA OB =13=33,∴∠ABO =30°,∴PE =12PB ,∴12PB +PD =PD +PE ≥DF ,当点P 在P 时,PD +PE 最小,最大值等于DF ,在Rt △ADF 中,∠DAF =90°-∠ABO =60°,AD =OD +PA =12+1=32,∴DF =AD ⋅sin ∠DAE =32×32-334,∴12PB +PD 最小=DF =334,故选:A .【点睛】本题以二次函数为背景,考查了二次函数与一元二次方程之间的关系,解直角三角形等知识,解决问题的关键是用三角函数构造12PB .3(2023秋·浙江金华·九年级统考期末)如图,正方形ABCD 的边长为4,点E 是正方形ABCD 内的动点,点P 是BC 边上的动点,且∠EAB =∠EBC .连结AE ,BE ,PD ,PE ,则PD +PE 的最小值为()3A.213-2B.45-2C.43-2D.215-2【答案】A【分析】先证明∠AEB =90°,即可得点E 在以AB 为直径的半圆上移动,设AB 的中点为O ,作正方形ABCD 关于直线BC 对称的正方形CFGB ,则点D 的对应点是F ,连接FO 交BC 于P ,交半圆O 于E ,根据对称性有:PD =PF ,则有:PE +PD =PE +PF ,则线段EF 的长即为PE +PD 的长度最小值,问题随之得解.【详解】解:∵四边形ABCD 是正方形,∴∠ABC =90°,∴∠ABE +∠EBC =90°,∵∠EAB =∠EBC ,∴∠EAB +∠EBA =90°,∴∠AEB =90°,∴点E 在以AB 为直径的半圆上移动,如图,设AB 的中点为O ,作正方形ABCD 关于直线BC 对称的正方形CFGB ,则点D 的对应点是F ,连接FO 交BC 于P ,交半圆O 于E ,根据对称性有:PD =PF ,则有:PE +PD =PE +PF ,则线段EF 的长即为PE +PD 的长度最小值,E∵∠G =90°,FG =BG =AB =4,∴OG =6,OA =OB =OE =2,∴OF =FG 2+OG 2=213,∴EF =OF -OE =213-2,故PE +PD 的长度最小值为213-2,故选:A .【点睛】本题考查了轴对称-最短路线问题,正方形的性质,勾股定理,正确的作出辅助线,得出点E 的运动路线是解题的关键.4(2022秋·安徽池州·九年级统考期末)如图,Rt △ABC 中,∠C =90°,AC =4,BC =3,点P 为AC 边上的动点,过点P 作PD ⊥AB 于点D ,则PB +PD 的最小值为()4 A.154 B.245 C.5 D.203【答案】B【分析】作点B 关于AC 的对称点B ,过点B 作B D ⊥AB 于点D ,交AC 于点P ,点P 即为所求作的点,此时PB +PD 有最小值,连接AB ,根据对称性的性质,可知:BP =B P ,△ABC ≅△AB C ,根据S △ABB =S △ABC +S △AB C =2S △ABC ,即可求出PB +PD 的最小值.【详解】解:如下图,作点B 关于AC 的对称点B ,过点B 作B D ⊥AB 于点D ,交AC 于点P ,连接AB ,点P 即为所求作的点,此时PB +PD 有最小值,根据对称性的性质,可知:BP =B P ,在Rt △ABC 中,∠ACB =90°,AC =4,BC =3,∴AB =AC 2+BC 2=5,根据对称性的性质,可知:△ABC ≅△AB C ,∴S △ABB =S △ABC +S △ABC =2S △ABC ,即12×AB ⋅B D =2×12BC ⋅AC ,∴5B D =24,∴B D =245,故选:B .【点睛】本题考查了轴对称一最短路线问题,解题的关键是掌握轴对称的性质.5(2023秋·甘肃定西·八年级校考期末)如图所示,在△ABC 中,∠ABC =68°,BD 平分∠ABC ,P 为线段BD 上一动点,Q 为 边AB 上一动点,当AP +PQ 的值最小时,∠APB 的度数是()A.118°B.125°C.136°D.124°【答案】D【分析】先在BC 上截取BE =BQ ,连接PE ,证明△PBQ ≌△PBE SAS ,得出PE =PQ ,说明AP +PQ =AP +PE ,找出当A 、P 、E 在同一直线上,且AE ⊥BC 时,AP +PE 最小,即AP +PQ 最小,过点A 作AE ⊥BC 于点E ,交BD 于点P ,根据三角形外角的性质可得答案.【详解】解:在BC 上截取BE =BQ ,连接PE ,如图:∵BD 平分∠ABC ,∠ABC =68°,∴∠ABD =∠CBD =12∠ABC =34°,∵BP =BP ,∴△PBQ ≌△PBE SAS ,∴PE =PQ ,∴AP +PQ =AP +PE ,∴当A 、P 、E 在同一直线上,且AE ⊥BC 时,AP +PE 最小,即AP +PQ最小,过点A作AE ⊥BC 于点E ,交BD 于点P ,如图:∵∠AEB =90°,∠CBD =34°,∴∠APB =∠AEB +∠CBD =124°.故选:D .5【点睛】本题主要考查了角平分线的定义,三角形全等的判定和性质,垂线段最短,三角形内角和定理与三角形的外角的性质,解题的关键是找出使AP +PQ 最小时点P 的位置.6(2022秋·重庆沙坪坝·八年级重庆市凤鸣山中学校联考期末)如图,E 为正方形ABCD 边AD 上一点,AE =1,DE =3,P 为对角线BD 上一个动点,则PA +PE 的最小值为()A.5B.42C.210D.10【答案】A【分析】连接EC 交BD 于P 点,根据“两点之间线段最短”,可知PA +PE 的最小值即为线段EC 的长,求出EC 的长即可.【详解】连接EC ,交BD 于P 点∵四边形ABCD 为正方形∴A 点和C 点关于BD 对称∴PA =PC∴PA +PE =PC +PE =EC根据“两点之间线段最短”,可知PA +PE 的最小值即为线段EC 的长.∵AE =1,DE =3∴AD =4∴DC =4∴CE =DE 2+CD 2=32+42=5∴PA +PE 的最小值为5故选:A【点睛】本题主要考查了正方形的性质和两点之间线段最短,这是一个将军饮马模型.熟练掌握正方形的性质并且能够识别出将军饮马模型是解题的关键.7(2023春·湖南张家界·八年级统考期中)如图,正方形ABCD 的边长为4,点M 在DC 上,且DM =1,N 是AC 上一动点,则DN +MN 的最小值为()A.4B.42C.25D.5【答案】D【分析】由正方形的对称性可知点B 与D 关于直线AC 对称,连接BM 交AC 于N ′,N ′即为所求在Rt △BCM 中利用勾股定理即可求出BM 的长即可.【详解】∵四边形ABCD 是正方形,∴点B 与D 关于直线AC 对称,6连接BD ,BM 交AC 于N ′,连接DN ′,∴当B 、N 、M 共线时,DN +MN 有最小值,则BM 的长即为DN +MN 的最小值,∴AC 是线段BD 的垂直平分线,又∵CD =4,DM =1∴CM =CD -DM =4-1=3,在Rt △BCM 中,BM =CM 2+BC 2=32+42=5故DN +MN 的最小值是5.故选:D .【点睛】本题考查的是轴对称-最短路线问题及正方形的性质,先作出D 关于直线AC 的对称点,由轴对称及正方形的性质判断出D 的对称点是点B 是解答此题的关键.8(2022秋·浙江杭州·九年级杭州外国语学校校考开学考试)如图,在平面直角坐标系中,二次函数y =-x 2+bx +3的图像与x 轴交于A 、C 两点,与x 轴交于点C (3,0),若P 是x 轴上一动点,点D 的坐标为(0,-1),连接PD ,则2PD +PC 的最小值是()A.4B.2+22C.22D.32+232【答案】A【分析】过点P 作PJ ⊥BC 于J ,过点D 作DH ⊥BC 于H ,根据2PD +PC =2PD +22PC =2PD +PJ ,求出DP +PJ 的最小值即可解决问题.【详解】解:连接BC ,过点P 作PJ ⊥BC 于J ,过点D 作DH ⊥BC 于H .∵二次函数y =-x 2+bx +3的图像与x 轴交于点C (3,0),∴b =2,∴二次函数的解析式为y =-x 2+2x +3,令y =0,-x 2+2x +3=0,解得x =-1或3,∴A (-1,0),令x =0,y =3,∴B (0,3),∴OB =OC =3,∵∠BOC =90°,∴∠OBC =∠OCB =45°,∵D(0,-1),∴OD =1,BD =4,∵DH ⊥BC ,∴∠DHB =90°,设DH =x ,则BH =x ,∵DH 2+BH 2=BD 2,7∴x =22,∴DH =22,∵PJ ⊥CB ,∴∠PJC =90°,∴PJ =22PC ,∴2PD +PC =2PD +22PC =2PD +PJ ,∵DP +PJ ≥DH ,∴DP +PJ ≥22,∴DP +PJ 的最小值为22,∴2PD +PC 的最小值为4.故选:A .【点睛】本题考查了二次函数的相关性质,以及等腰直角三角形的判定和性质,垂线段最短等知识,得到∠OBC =∠OCB =45°,PJ =22PC 是解题的关键.9(2022·山东泰安·统考中考真题)如图,四边形ABCD 为矩形,AB =3,BC =4.点P 是线段BC 上一动点,点M 为线段AP 上一点.∠ADM =∠BAP ,则BM 的最小值为()A.52 B.125 C.13-32 D.13-2【答案】D【分析】证明∠AMD =90°,得出点M 在O 点为圆心,以AO 为半径的圆上,从而计算出答案.【详解】设AD 的中点为O ,以O 点为圆心,AO 为半径画圆∵四边形ABCD 为矩形∴∠BAP +∠MAD =90°∵∠ADM =∠BAP∴∠MAD +∠ADM =90°∴∠AMD =90°∴点M 在O 点为圆心,以AO 为半径的圆上连接OB 交圆O 与点N∵点B 为圆O 外一点∴当直线BM 过圆心O 时,BM 最短∵BO 2=AB 2+AO 2,AO =12AD =2∴BO 2=9+4=13∴BO =13∵BN =BO -AO =13-2故选:D .【点睛】本题考查直角三角形、圆的性质,解题的关键是熟练掌握直角三角形和圆的相关知识.810(2022·河南·校联考三模)如图1,正方形ABCD 中,点E 是BC 的中点,点P 是对角线AC 上的一个动点,设AP =x ,PB +PE =y ,当点P 从A 向点C 运动时,y 与x 的函数关系如图2所示,其中点M 是函数图象的最低点,则点M 的坐标是()A.42,35B.22,35C.35,22D.35,42【答案】A【分析】根据图像,当P 与C 重合时,PB +PE =9即CB +CE =9,从而确定正方形的边长为6,根据将军饮马河原理,连接DE 交AC 于点G ,当点P 与点G 重合时,PE +PB 最小,且为DE 的长即点M 的纵坐标,利用相似三角形,计算AG 的长即为横坐标.【详解】如图,根据图像,当P 与C 重合时,PB +PE =9即CB +CE =9,∵点E 是BC 的中点,∴BC =6,连接DE 交AC 于点G ,当点P 与点G 重合时,PE +PB 最小,且为DE 的长即点M 的纵坐标,∵四边形ABCD 是正方形,AB =6,∴CE ∥AD ,AC =62+62=62,DE =62+32=35,∴△CGE ∽△AGD ,∴CG AG =CE AD =12,∴AC AG=32,∴AG =42,故点M 的坐标为(42,35),故A 正确.故选:A .【点睛】本题考查了正方形的性质,三角形相似的判定和性质,函数图像信息的获取,将军饮马河原理,熟练掌握正方形的性质,灵活运用三角形相似,构造将军饮马河模型求解是解题的关键.2二、填空题11(2023春·江苏宿迁·九年级校联考阶段练习)如图,矩形ABCD ,AB =4,BC =8,E 为AB 中点,F 为直线BC 上动点,B 、G 关于EF 对称,连接AG ,点P 为平面上的动点,满足∠APB =12∠AGB ,则DP 的最小值.【答案】210-22【分析】由题意可知,∠AGB =90°,可得∠APB =12∠AGB =45°,可知点P 在以AB 为弦,圆周角∠APB =45°的9圆上,(要使DP 最小,则点P 要靠近蒂点D ,即点P 在AB 的右侧),设圆心为O ,连接OA ,OB ,OE ,OP ,OD ,过点O 作OQ ⊥AD ,可知△AOB 为等腰直角三角形,求得OA =22AB =22=OP ,AQ =OQ =22OA =2,QD =AD -AQ =6,OD =OQ 2+QD 2=210,再由三角形三边关系可得:DP ≥OD -OP =210-22,当点P 在线段OD 上时去等号,即可求得DP 的最小值.【详解】解:∵B 、G 关于EF 对称,∴BH =GH ,且EF ⊥BG∵E 为AB 中点,则EH 为△ABG 的中位线,∴EH ∥AG ,∴∠AGB =90°,∵∠APB =12∠AGB ,即∠APB =12∠AGB =45°,∴点P 在以AB 为弦,圆周角∠APB =45°的圆上,(要使DP 最小,则点P 要靠近蒂点D ,即点P 在AB 的右侧)设圆心为O ,连接OA ,OB ,OE ,OP ,OD ,过点O 作OQ ⊥AD ,则OA =OB =OP ,∵∠APB =45°,∴∠AOB =90°,则△AOB 为等腰直角三角形,∴OA =22AB =22=OP ,又∵E 为AB 中点,∴OE ⊥AB ,OE =12AB =AE =BE ,又∵四边形ABCD 是矩形,∴∠BAD =90°,AD =BC =8,∴四边形AEOQ 是正方形,∴AQ =OQ =22OA =2,QD =AD -AQ =6,∴OD =OQ 2+QD 2=210,由三角形三边关系可得:DP ≥OD-OP =210-22,当点P 在线段OD 上时去等号,∴DP 的最小值为210-22,故答案为:210-22.【点睛】本题考查轴对称的性质,矩形的性质,隐形圆,三角形三边关系,正方形的判定及性质,等腰直角三角形的判定及性质,根据∠APB =12∠AGB =45°得知点P 在以AB 为弦,圆周角∠APB =45°的圆上是解决问题的关键.12(2023春·江苏连云港·八年级期中)如图,在边长为8的正方形ABCD 中,点G 是BC 边的中点,E 、F 分别是AD 和CD 边上的点,则四边形BEFG 周长的最小值为.【答案】2410【分析】作点G 关于CD 的对称点G ,作点B 关于AD 的对称点B ,连接B G ,根据两点之间线段最短即可解决问题.【详解】作点G 关于CD 的对称点G ,作点B 关于AD 的对称点B ,连接B G∵EB =EB ,FG =FG ,∴BE +EF +FG +BG =B E +EF +FG +BG ,∵EB +EF +FG ≥B G ,∴四边形BEFG 的周长的最小值=BG +B G ,∵正方形ABCD 的边长为8∴BG =4,BB =16,BG =12,∴B G =162+122=20,∴四边形BEFG 的周长的最小值为=4+20=24.故答案为:24.【点睛】本题考查轴对称求线段和的最短问题,正方形的性质,勾股定理,解题的关键是学会利用轴对称解决最短问题.13(2022·湖南湘潭·校考模拟预测)如图,菱形草地ABCD 中,沿对角线修建60米和80米两条道路AC <BD ,M 、N 分别是草地边BC 、CD 的中点,在线段BD 上有一个流动饮水点P ,若要使PM +PN 的距离最短,则最短距离是米.【答案】50【分析】作M 关于BD 的对称点Q ,连接NQ ,交BD 于P ,连接MP ,当P 点与P 重合时,MP +NP =MP +NP =NQ 的值最小,根据菱形的性质和勾股定理求出BC 长,即可得出答案.【详解】解:作M 关于BD 的对称点Q ,连接NQ ,交BD 于P ,连接MP ,当P 点与P 重合时,MP +NP =MP +NP =NQ 的值最小,∵四边形ABCD 是菱形,∴AC ⊥BD ,∠QBP =∠MBP ,即Q 在AB 上,∵MQ ⊥BD ,∴AC ∥MQ ,∴M 为BC 中点,∴Q 为AB 中点,∵N 为CD 中点,四边形ABCD 是菱形,∴BQ ∥CD ,BQ =CN ,∴四边形BQNC 是平行四边形,∴NQ =BC ,设AC 与BD 的交点为点O ,∵四边形ABCD 是菱形,∴AC ⊥BD,OC =12AC =30米,OB =12BD =40米,∴BC =OB 2+OC 2=50米,∴PM +PN 的最小值是50米.故答案为:50.11【点睛】本题考查了轴对称-最短路线问题,平行四边形的性质和判定,菱形的性质,勾股定理的应用,解此题的关键是能根据轴对称找出P 的位置.14(2023春·江苏·九年级校考阶段练习)如图,正方形ABCD 的边长为4,⊙B 的半径为2,P 为⊙B 上的动点,则2PC -PD 的最大值是.【答案】2【分析】解法1,如图:以PD 为斜边构造等腰直角三角形△PDM ,连接MC ,BD ,连接PM 、DM ,推得2PC -PD=2PC -22PD =2PC -PM ,因为PC -PM ≤MC ,求出MC 即可求出答案.解法2:如图:连接BD 、BP 、PC ,在BD 上做点M ,使BM BP =24,连接MP ,证明△BMP ∼△BPD ,在BC 上做点N ,使BN BP=12,连接NP ,证明△BNP ∼△BPC ,接着推导出2PC -PD =22MN ,最后证明△BMN ∼△BCD ,即可求解.【详解】解法1如图:以PD 为斜边构造等腰直角三角形△PDM ,连接MC ,BD ,∴∠PDM =45,DM =PM =22PD ,∵四边形ABCD 正方形∴∠BDC =45°,DB DC=2又∵∠PDM =∠PDB +MDB ,∠BDC =∠MDB +MDC∴∠PDB =∠MDC在△BPD 与△MPC 中∠PDB =∠MDC ,DB DC=DP DM =2∴△BPD ∼△MPC∴PB MC=2∵BP =2∴MC =2∵2PC -PD =2PC-22PD =2PC -PM ∵PC -PM ≤MC ∴2PC -PD =2PC -PM ≤2MC =2故答案为:2.解法2如图:连接BD 、BP 、PC根据题意正方形ABCD 的边长为4,⊙B 的半径为2∴BP =2,BD =BC 2+CD 2=42+42=42∵BP BD =242=2412在BD 上做点M ,使BM BP=24,则BM =22,连接MP 在△BMP 与△BPD 中∠MBP =∠PBD ,BP BD =BM BP∴△BMP ∼△BPD∴PM PD =24,则PD =22PM ∵BP BC =24=12在BC 上做点N ,使BN BP=12,则BN =1,连接NP 在△BNP 与△BPC 中∠NBP =∠PBC ,BN BP =BP PC∴△BNP ∼△BPC∴PN PC=12,则PC =2PN ∴如图所示连接NM ∴2PC -PD =2×2PN -22PM =22PN -PM ∵PN -PM ≤NM ∴2PC -PD =22PN -PM ≤22NM在△BMN 与△BCD 中∠NBM=∠DBC ,BM BC =224=28,BN BD =142=28∴BM BC=BN BD ∴△BMN ∼△BCD∴MN CD=28∵CD =4∴MN =22∴22MN =22×22=2∴2PC -PD ≤22NM =2故答案为:2.【点睛】本题考查正方形的性质,相似三角形,勾股定理等知识,难度较大,熟悉以上知识点运用是解题关键.15(2023秋·广东广州·九年级统考期末)如图,四边形ABCD 中,AB ∥CD ,AC ⊥BC ,∠DAB =60°,AD =CD =4,点M 是四边形ABCD 内的一个动点,满足∠AMD =90°,则△MBC 面积的最小值为.【答案】63-4【分析】取AD 的中点O ,连接OM ,过点M 作ME ⊥BC 交BC 的延长线于点E ,过点O 作OF ⊥BC 于F ,交CD 于G ,则OM +ME ≥OF ,通过计算得出当O ,M ,E 三点共线时,ME 有最小值,求出最小值即可.【详解】解:如图,取AD 的中点O ,连接OM ,过点M 作ME ⊥BC 交BC 的延长线于点E ,过点O 作OF ⊥BC 于F ,交CD 于G ,则13OM +ME ≥OF ,∵AB ∥CD ,∠DAB =60°,AD =CD =4,∴∠ADC =120°,∵AD =CD ,∴∠DAC =30°,∴∠CAB =30°,∵AC ⊥BC ,∴∠ACB =90°∴∠B =90°-30°=60°,∴∠B =∠DAB ,∴四边形ABCD 为等腰梯形,∴BC =AD =4,∵∠AMD =90°,AD =4,OA =OD ,∴OM =12AD =2,∴点M 在以点O 为圆心,2为半径的圆上,∵AB ∥CD ,∴∠GCF =∠B =60°,∴∠DGO =∠CGF =30°,∵OF ⊥BC ,AC ⊥BC ,∴∠DOG =∠DAC =30°=∠DGO ,∴DG =DO =2,∴OG =2OD ⋅cos30°=23,GF =3,OF =33,∴ME ≥OF -OM =33-2,∴当O ,M ,E 三点共线时,ME 有最小值33-2,∴△MBC 面积的最小值为=12×4×33-2 =63-4.【点睛】本题考查了解直角三角形、隐圆、直角三角形的性质等知识点,点M 位置的确定是解题关键.16(2023春·全国·八年级专题练习)如图,在等边△ABC 中,BD ⊥AC 于D ,AD =3cm .点P ,Q 分别为AB,AD 上的两个定点且BP =AQ =1cm ,点M 为线段BD 上一动点,连接PM ,QM ,则PM +QM 的最小值为cm .【答案】5【分析】如图所示,作点P 关于BD 的对称点P ,且点P 在BC 上,则PM +QM =P M+QM ,当P ,M ,Q 在同一条直线上时,有最小值,证明四边形PP QA 是平行四边形,P Q =AP =AB -BP ,由此即可求解.【详解】解:如图所示,作点P 关于BD 的对称点P ,∵△ABC 是等边三角形,BD ⊥AC ,∴∠ABD =∠DBC =12∠ABC =12×60°=30°,14∴点P 在BC 上,∴P M =PM ,则PM +QM =P M +QM ,当P ,M ,Q 在同一条直线上时,有最小值,∵点P 关于BD 的对称点P ,∠ABD =∠DBC =30°,∴PP ⊥BM ,BP =BP =1cm ,∴∠BP P =60°,∴△BPP 是等边三角形,即∠BP P =∠C =60°,∴PP ∥AC ,且PP =AQ =1cm ,∴四边形PP QA 是平行四边形,∴P Q =AP =AB -BP ,在Rt △ABD 中,∠ABD =30°,AD =3,∴AB =2AD =2×3=6,∴AP =P Q =P M +QM =PM +QM =AB -BP =6-1=5,故答案为:5.【点睛】本题主要考查动点与等边三角形,对称-最短路径,平行四边形的判定和性质的综合,理解并掌握等边三角形得性质,对称-最短路径的计算方法,平行四边形的判定和性质是解题的关键.17(2022秋·山东菏泽·九年级校考阶段练习)如图,在周长为12的菱形ABCD 中,DE =1,DF =2,若P 为对角线AC 上一动点,则EP +FP 的最小值为.【答案】3【分析】作F 点关于BD 的对称点F ,连接EF 交BD 于点P ,则PF =PF ,由两点之间线段最短可知当E 、P 、F 在一条直线上时,EP +FP 有最小值,然后求得EF 的长度即可.【详解】解:作F 点关于BD 的对称点F ,则PF =PF ,连接EF '交BD 于点P .∴EP +FP =EP +F P .由两点之间线段最短可知:当E 、P 、F '在一条直线上时,EP +FP 的值最小,此时EP +FP =EP +F P =EF .∵四边形ABCD 为菱形,周长为12,∴AB =BC =CD =DA =3,AB ∥CD ,∵AF =2,AE =1,∴DF =AE =1,∴四边形AEF D 是平行四边形,∴EF =AD =3.∴EP +FP 的最小值为3.故答案为:3.【点睛】本题主要考查的是菱形的性质、轴对称--路径最短问题,明确当E 、P 、F 在一条直线上时EP +FP 有最小值是解题的关键.18(2023春·上海·八年级专题练习)如图,直线y =x +4与x 轴,y 轴分别交于A和B ,点C 、D 分别为线段AB 、OB 的中点,P 为OA 上一动点,当PC +PD 的值最小时,点P 的坐标为.15【答案】(-1,0)【分析】直线y =x +4与x 轴,y 轴分别交于A 和B ,可求出点A ,B 的坐标,点C 、D 分别为线段AB 、OB 的中点,可求出点C 、D 的坐标,作点C 关于x 轴的对称点C ,连接C D 与x 轴的交点就是所求点P 的坐标.【详解】解:直线y =x +4与x 轴,y 轴分别交于A 和B ,∴当y =0,x =-4,即A (-4,0);当x =0,y =4,即B (0,4),∵点C 、D 分别为线段AB 、OB 的中点,∴C (-2,2),D (0,2),如图所示,过点C 关于x 轴的对称点C,∴C (-2,-2),∴直线C D 的解析式为:y =2x +2,当y =0,x =-1,即P (-1,0),故答案为:(-1,0).【点睛】本题主要考查一次函数与最短线段的综合,掌握对称中最短线段的解题方法是解题的关键.19(2023秋·黑龙江鸡西·九年级统考期末)如图,抛物线y =x 2-4x +3与x 轴分别交于A ,B两点(点A 在点B 的左侧),与y 轴交于点C ,在其对称轴上有一动点M ,连接MA ,MC ,AC ,则△MAC 周长的最小值是.【答案】32+10【分析】根据“将军饮马”模型,先求出A 1,0 ,B 3,0 ,C 0,3 ,由二次函数对称性,A ,B 关于对称轴对称,从而C △MAC =CA +CM +MA =CA +CM +MB ,AC =OA 2+OC 2=10,则△MAC 周长的最小值就是CM +MB 的最小值,根据两点之间线段最短即可得到CM +MB 的最小值为C ,M ,B 三点共线时线段CB 长,从而得到CB =OC 2+OB 2=32,即可得到答案.【详解】解:∵抛物线y =x 2-4x +3与x 轴分别交于A ,B 两点(点A 在点B 的左侧),与y 轴交于点C ,16∴当y =0时,0=x 2-4x +3解得x =1或x =3,即A 1,0 ,B 3,0 ;当x =0时,y =3,即C 0,3 ,由二次函数对称性,A ,B 关于对称轴对称,即MA =MB ,∴C △MAC =CA +CM +MA =CA +CM +MB ,∵AC =OA 2+OC 2=10,∴△MAC 周长的最小值就是CM +MB 的最小值,根据两点之间线段最短即可得到CM +MB 的最小值为C ,M ,B 三点共线时线段CB 长,∵CB =OC 2+OB 2=32,∴△MAC 周长的最小值为CA +CB =32+10,故答案为:32+10.【点睛】本题考查动点最值问题与二次函数综合,涉及“将军饮马”模型求最值、二次函数图像与性质、解一元二次方程、勾股定理求线段长等知识,熟练掌握动点最值的常见模型是解决问题的关键.20(2023秋·浙江温州·九年级校考期末)如图所示,∠ACB =60°,半径为2的圆O 内切于∠ACB.P 为圆O 上一动点,过点P 作PM 、PN 分别垂直于∠ACB 的两边,垂足为M 、N ,则PM +2PN 的取值范围为.【答案】6-23≤PM +2PN ≤6+23【分析】根据题意,本题属于动点最值问题-“阿氏圆”模型,首先作MH ⊥NP 于H ,作MF ⊥BC 于F ,如图所示,通过代换,将PM +2PN 转化为PN +12PM =PN +HP =NH ,得到当MP 与⊙O 相切时,MF 取得最大值和最小值,分两种情况,作出图形,数形结合解直角三角形即可得到相应最值,进而得到取值范围.【详解】解:作MH ⊥NP 于H ,作MF ⊥BC 于F ,如图所示:∵PM ⊥AC ,PN ⊥CB ,∴∠PMC =∠PNC =90°,∴∠MPN =360°-∠PMC -∠PNC -∠C =120°,∴∠MPH =180°-∠MPN =60°,∴HP =PM ⋅cos ∠MPH =PM ⋅cos60°=12PM ,∴PN +12PM =PN +HP =NH ,∵MF =NH ,∴当MP 与⊙O 相切时,MF 取得最大和最小,①连接OP ,OG ,OC ,如图1所示:可得:四边形OPMG 是正方形,∴MG =OP =2,在Rt △COG 中,CG =OG ⋅tan60°=23,∴CM =CG +GM =2+23,在Rt △CMF 中,MF =CM ⋅sin60°=3+3,∴HN =MF =3+3,即PM +2PN =212PM +PN =2HN =6+23;②连接OP ,OG ,OC ,如图2所示:可得:四边形OPMG 是正方形,17∴MG =OP =2,由上同理可知:在Rt △COG 中,CG =OG ⋅tan60°=23,∴CM =CG -GM =23-2,在Rt △CMF 中,MF =CM ⋅sin60°=3-3,∴HN =MF =3-3,即PM +2PN =212PM +PN =2HN =6-23,∴6-23≤PM +2PN ≤6+23.故答案为:6-23≤PM +2PN ≤6+23.【点睛】本题考查动点最值模型-“阿氏圆”,难度较大,掌握解决动点最值问题的方法,熟记相关几何知识,尤其是圆的相关知识是解决问题的关键.3三、解答题21(2022春·江苏·九年级专题练习)综合与探究如图,已知抛物线y =ax 2+bx +4经过A -1,0 ,B 4,0 两点,交y 轴于点C .(1)求抛物线的解析式,连接BC ,并求出直线BC 的解析式;(2)请在抛物线的对称轴上找一点P ,使AP +PC 的值最小,此时点P 的坐标是;(3)点Q 在第一象限的抛物线上,连接CQ ,BQ ,求出△BCQ 面积的最大值.【答案】(1)y =-x 2+3x +4;y =-x +4(2)32,52(3)8【分析】(1)将A -1,0 ,B 4,0 两点,代入抛物线解析式,可得到抛物线解析式,从而得到C 0,4 ,再设直线BC 的解析式为y =kx +b k ≠0 ,把点B 、C 的坐标代入,即可求解;(2)连接BC ,PB ,根据题意可得A 、B 关于抛物线的对称轴直线x =32对称,从而得到当P 在直线AB 上三点共线时,AP +CP 的值最小,把x =32代入直线BC 的解析式,即可求解;(3)过Q 作QD ⊥x 轴,交BC 于D ,设Q d ,-d 2+3d +4 ,其中0≤d ≤4,则D d ,-d +4 ,可得QD =-d 2+4d ,从而得到S ΔBCQ =12OB ×QD =-2d -2 2+8,即可求解;【详解】(1)解:(1)∵抛物线y =ax 2+bx +4经过A -1,0 ,B 4,0 两点,∴a -b +4=016a +4b +4=0,解得:a =-1b =3 ,18∴抛物线的解析式为y =-x 2+3x +4;∵抛物线与y 轴的交点为C ,∴C 0,4 ,设直线BC 的解析式为y =kx +b k ≠0 ,把点B 、C 的坐标代入得:4k +b =0b =4 ,解得:k =-1b =4 ,∴直线BC 的解析式为y =-x +4;(2)如图,连接BC ,PB ,∵y =-x 2+3x +4=-x -32 2+74,∴抛物线的对称轴为直线x =32,根据题意得:A 、B 关于抛物线的对称轴直线x =32对称,∴AP =BP ,∴AP +CP =BP +CP ≥BC ,即当P 在直线AB 上时,AP +CP 的值最小,∴当x =32时,y =-32+4=52,∴P 32,52 ,故答案是:32,52 ;(3)过Q 作QD ⊥x 轴,交BC 于D ,设Q d ,-d 2+3d +4 ,其中0≤d ≤4,则D d ,-d +4 ,∴QD =-d 2+3d +4 --d +4 =-d 2+4d ,∵B 4,0 ,∴OB =4,∴S ΔBCQ =12OB ×QD =-2d 2+8d =-2d -2 2+8,当d =2时,S ΔBCQ 取最大值,最大值为8,∴△BCQ 的最大面积为8;【点睛】本题主要考查了二次函数的图像和性质,利用数形结合思想和分类讨论思想是解题的关键.22(2023秋·江苏淮安·八年级统考期末)如图1,直线AB :y =-x +6分别与x ,y 轴交于A ,B 两点,过点B 的直线交x 轴负半轴于点C -3,0 .(1)请直接写出直线BC 的关系式:(2)在直线BC 上是否存在点D,使得S △ABD =S △AOD 若存在,求出点D 坐标:若不存请说明理由;(3)如图2,D 11,0 ,P 为x 轴正半轴上的一动点,以P 为直角顶点、BP 为腰在第一象限内作等腰直角三角形△BPQ ,连接QA ,QD .请直接写出QB -QD 的最大值:.19【答案】(1)y =2x +6(2)当D 185,665 或D -185,-65时,S △ABD =S △AOD (3)37【分析】(1)根据直线AB 与y 轴的交点,可求出点B 的坐标,再用待定系数法即可求解;(2)设D (a ,2a +6),分别用含a 的式子表示出出S △AOD ,S △ABD ,由此即可求解;(3)△BPQ 是等腰直角三角形,设P (m ,0)(m >0),可表示出QB ,再证Rt △BOP ≌Rt △PTQ (AAS ),如图所示,当点B ,R ,Q 在一条直线上时,QB -QD 的值最大,最大值为BR 的值,可求得点R 的坐标,根据勾股定理即可求解.【详解】(1)解:∵直线AB :y =-x +6分别与x ,y 轴交于A ,B 两点,令x =0,则y =6,∴B (0,6),且C -3,0 ,设直线BC 的解析式为y =kx +b ,∴b =6-3k +b =0,解得,k =2b =6 ,∴直线BC 的解析式为y =2x +6,故答案为:y =2x +6.(2)解:由(1)可知直线BC 的解析式为y =2x +6,直线AB 的解析式为y =-x +6,∴A (6,0),B (0,6),C (-3,0),∴OA =6,BO =6,OC =3,如图所示,点D 在直线BC 上,过点D 作DE ⊥x 轴于E ,∴设D (a ,2a +6),E (a ,0),∴S △ABC =12AC ·OB =12×(6+3)×6=27,S △ADC =12AC ·DE =12×(6+3)×a =92a ,S △AOD =12OA ·DE =12×6×a =3a ,∴S △ABD =S △ABC -S △ADC =27-92a ,若S △ABD =S △AOD ,则27-92a =3a ,当a >0时,27-92a =3a ,解得,a =185,即D 185,665 ;当a <0时,27+92a =-3a ,解得,a =-185,即D -185,-65 ;综上所述,当D 185,665 或D -185,-65时,S △ABD =S △AOD .(3)解:已知A (6,0),B (0,6),D (11,0),设P (m ,0)(m >0),∴在Rt △BOP 中,OB =6,OP =m ,∵△BPQ 是等腰直角三角形,∠BPQ =90°,∴BP =QP ;如图所示,过点Q 作QT ⊥x 轴于T ,20在Rt △BOP ,Rt △PTQ 中,∠BOP =∠PTQ =90°,∠BPO +∠QPA =∠QPA +∠PQT =90°,∴∠BPO =∠PQT ,∴∠BPO =∠PQT∠BOP =∠PTQ BP =QP,∴Rt △BOP ≌Rt △PTQ (AAS ),∴OP =TQ =m ,OB =PT =6,∴AT =OP +PT -OA =m +6-6=m ,∴AT =QT ,且QT ⊥x 轴,∴△ATQ 是等腰直角三角形,∠QAT =45°,则点Q 的轨迹在射线AQ 上,如图所示,作点D 关于直线AQ 的对称点R,连接QR ,BR ,AR ,A (6,0),B (0,6),D (11,0),∵△ATQ 是等腰直角三角形,即∠QAT =45°,根据对称性质,∴∠QAR =45°,∴RA ⊥x 轴,且△DQA ≌△RQA ,∴AR =AD =11-6=5,则R (6,5),如图所示,当点B ,R ,Q 在一条直线上时,QB -QD 的值最大,最大值为BR 的值;∴由勾股定理得:BR =62+(6-5)2=37,故答案为:37.【点睛】本题主要考查一次函数,几何的综合,掌握待定系数法求解析式,将军饮马问题,等腰直角三角形的性质,勾股定理是解题的关键.23(2023春·重庆沙坪坝·九年级重庆八中校考阶段练习)△ABC 中,∠B =60°.(1)如图1,若AC >BC ,CD 平分∠ACB 交AB 于点D ,且AD =3BD .证明:∠A =30°;(2)如图2,若AC <BC ,取AC 中点E ,将CE 绕点C 逆时针旋转60°至CF ,连接BF 并延长至G ,使BF =FG ,猜想线段AB 、BC 、CG 之间存在的数量关系,并证明你的猜想;(3)如图3,若AC =BC ,P 为平面内一点,将△ABP 沿直线AB 翻折至△ABQ ,当3AQ +2BQ +13CQ 取得最小值时,直接写出BPCQ的值.【答案】(1)见解析(2)BC =AB +CG ,理由见解析(3)213+33913【分析】(1)过点D 分别作BC ,AC 的垂线,垂足为E ,F ,易得DE =DF ,由∠B =60°,可得DE =DF =32BD ,由AD =3BD ,求得sin A =DE AD=12,可证得∠A =30°;(2)延长BA ,使得BH =BC ,连接EH ,CH ,易证△BCH 为等边三角形,进而可证△BCF ≌△HCE SAS ,可得BF =HE ,∠BFC =∠HEC ,可知∠AEH =∠CFG ,易证得△AEH ≌△CFG SAS ,可得AH =CG ,由BC =BH =AB +AH =AB +CG 可得结论;(3)由题意可知△ABC 是等边三角形,如图,作CM ⊥CA ,且CM =32CA ,作CN ⊥CQ ,且CN =32CQ ,可得CM CA=CN CQ =32,QN =CQ 2+CN 2=132CQ ,可知△ACQ ∽△MCN ,可得MN =32AQ ,由3AQ +2BQ +13CQ =232AQ +BQ +132CQ =2MN +BQ +QN ≥2BM 可知点Q ,N 都在线段BM 上时,3AQ +2BQ+13CQ 有最小值,过点C 作CR ⊥BM ,过点M 作MT ⊥BC 交BC 延长线于T ,可得CR =CQ ⋅sin ∠CQN =313CQ ,QR =CQ ⋅cos ∠CQN =213CQ ,可证△CBR ∽△MBT ,得BR CR =BT MT ,设BC =a 由等边三角形的性质,可得CM =32a ,进而可得CT =CM ⋅cos30°=334a ,MT =CM ⋅sin30°=34a ,结合BR CR=BTMT 可得:BQ +213CQ 313CQ =a +334a 34a ,可得BQ CQ =213+33913,由翻折可知,BP =BQ ,可求得BP CQ的值.【详解】(1)证明:过点D 分别作BC ,AC 的垂线,垂足为E ,F ,∵CD 平分∠ACB ,DE ⊥BC ,DF ⊥AC ,∴DE =DF ,又∵∠B =60°,∴DE =BD ⋅sin60°=32BD ,则DE =DF =32BD ,又∵AD =3BD ,∴sin A =DE AD =32BD3BD=12,∴∠A =30°;(2)BC =AB +CG ,理由如下:延长BA ,使得BH =BC ,连接EH ,CH ,∵∠ABC =60°,BH =BC ,∴△BCH 为等边三角形,∴CB =CH ,∠BCH =60°,∵CE 绕点C 逆时针旋转60°至CF ,∴CE =CF ,∠ECF =60°,则∠BCH -∠ACB =∠ECF -∠ACB ,∴∠ECH =∠FCB ,∴△BCF ≌△HCE SAS ,∴BF =HE ,∠BFC =∠HEC ,则∠AEH =∠CFG ,∵BF =FG ,∴BF =HE =FG ,又∵E 为AC 中点,∴AE =CE =CF ,∴△AEH ≌△CFG SAS ,∴AH =CG ,∴BC =BH =AB +AH =AB +CG ;(3)∵∠ABC =60°,AC =BC ,∴△ABC 是等边三角形,如图,作CM ⊥CA ,且CM =32CA ,作CN ⊥CQ ,且CN =32CQ ,则CM CA=CN CQ =32,QN =CQ 2+CN 2=132CQ ,∴sin ∠CQN =CN QN =313,cos ∠CQN =CQ QN =213,则∠ACM =∠QCN =90°,∴∠ACM -∠ACN =∠QCN -∠ACN ,则∠ACQ =∠MCN∴△ACQ ∽△MCN ,∴MN AQ =CM CA=32,即:MN =32AQ ,∴3AQ +2BQ +13CQ =232AQ +BQ +132CQ =2MN +BQ +QN ≥2BM即:点Q ,N 都在线段BM 上时,3AQ +2BQ +13CQ 有最小值,如下图,过点C 作CR ⊥BM ,过点M 作MT ⊥BC 交BC 延长线于T ,则∠BRC =∠BTM =90°,CR =CQ ⋅sin ∠CQN =313CQ ,QR =CQ ⋅cos ∠CQN =213CQ ,又∵∠CBR =∠MBT ,∴△CBR ∽△MBT ,∴BR CR=BT MT ,∵△ABC 是等边三角形,设BC =a ∴∠ACB =60°,AC =BC =a ,则CM =32a ,∵∠ACM =90°,∴∠MCT =30°,则CT =CM ⋅cos30°=334a ,MT =CM ⋅sin30°=34a ,则由BR CR=BT MT 可得:BQ +213CQ 313CQ =a +334a34a ,整理得:133BQ CQ +23=4+333,得BQ CQ=213+33913,由翻折可知,BP =BQ ,∴BP CQ =BQ CQ=213+33913.【点睛】本题属于几何综合,考查了解直角三角形,等边三角形的判定及性质,全等三角形的判定及性质,相似三角形的判定及性质,旋转的性质以及费马点问题,掌握费马点问题的解决方法,添加辅助线构造全等三角形和相似三角形是解决问题的关键.24(2023春·江苏·八年级专题练习)定义:既相等又垂直的两条线段称为“等垂线段”,如图1,在Rt △ABC 中,∠A =90°,AB =AC ,点D 、E 分别在边AB 、AC 上,AD =AE ,连接DE 、DC ,点M 、P 、N 分别为DE 、DC 、BC 的中点,且连接PM 、PN .(1)观察猜想线段PM 与PN 填(“是”或“不是”)“等垂线段”.(2)△ADE 绕点A 按逆时针方向旋转到图2所示的位置,连接BD ,CE ,试判断PM 与PN 是否为“等垂线段”,并说明理由.(3)拓展延伸把△ADE 绕点A 在平面内自由旋转,若DE =2,BC =4,请直接写出PM 与PN 的积的最大值.。

中考语文 词语、短语与成语 专项训练

中考语文词语、短语与成语专项训练本题型以选择题(四选一,从四个词语中选择使用恰当的、正确的、不恰当的、不正确的、错误的一项等)的形式考查,四个选项各自独立,内容都来自课外。

预测2023年词语的理解与运用还会延续这种命题形式。

但除了常见词语、成语外,还可能考查关联词语的使用、近义词的选用等。

在备考中,要加强对教材中词语、成语的理解和记忆,同时加强对关联词语、近义词和敬辞、谦辞等在语境中的辨析、运用能力的训练。

在平时的学习中,首先我们对于遇到的词语要做好积累,其次是注意可以从词义、词语的感情色彩、习惯用法等方面进行归纳。

成语常见的错误有:望文生义、褒贬不当、搭配不当、用错对象、重复冗赘、谦敬错位、自相矛盾、不合语境等;近义词可以从意义、色彩、用法等方面辨析;同一个句子运用不同的关联词,作用就不同,表达的意思也就不一样,究竟选用什么关联词,要根据语境的表达需要来确定。

近义词与同义词辨析;成语的理解与运用;结合语境解释词语;理解文章中的词语及生活中常见的词语;从感情色彩上分清褒义词、贬义词和中性词等是考查的热点与重点。

(含热点溯源和模拟预测)热点溯源1.(2022·贵州安顺·中考真题)下列各句中加点词语使用有误的一项是()。

A.同学们夸赞李华的文章旁征博引,文笔优美,他却谦虚地说这不过是妙手偶得....。

B.张桂梅老师身患重病却仍然坚守在教育一线,她为教育事业殚精竭虑....,深受师生爱戴。

C.疫情让餐馆老板王飞的生活变得拮据..,好在社区发放的物资基本保障了他的温饱需求。

D.随着人们环保意识不断增强,长江水质得到极大改善,濒临..灭绝的江豚数量有所增加。

【答案】A【解析】考查词语运用。

A.妙手偶得:技术高超的人,偶然间即可得到。

也用来形容文学素养很深的人,出于灵感,即可偶然间得到妙语佳作。

不能用于自身,用错对象;B.殚精竭虑:使尽了精力,费尽了心思。

正确;C.拮据:手头不宽裕,钱不够用。

初中中考 语文 文学常识专项训练及答案

一、中考语文专项练习:文学常识1.电影《一江春水向东流》的片名取自我国古代一位词人词作中的句子。

这位词人是()A. 辛弃疾B. 李煜C. 宴殊D. 李清照【答案】 B【解析】【分析】“问君能有几多愁?恰似一江春水向东流”出自五代李煜的《虞美人》。

故答案为:B【点评】《虞美人》是李煜的代表作,也是李后主的绝命词,在写下这首《虞美人》后,宋太宗恨其“故国不堪回首月明中”之词而毒死了他。

写的是处于“故国不堪回首”的境遇下,愁思难禁的痛苦。

全词不加藻饰,不用典故,纯以白描手法直接抒情,寓景抒情,通过意境的创造以感染读者,集中地体现了李煜词的艺术特色。

以“一江春水向东流”比愁思不尽,贴切感人。

2.下列文学常识说法不正确的一项是()A. 《诗经》是我国是最早的一部诗歌总集,收录了诗歌305篇,分为“风”“雅”“颂”三部分,“风”又叫“国风”。

B. 杜甫的《春望》、白居易的《钱塘湖春行》和韩愈的《早春呈水部张十八员外》,都侧重表达了诗人对春天景物的美好感受,处处洋溢着对大好春光的欣赏、赞美之情。

C. “千古诗才,蓬莱文章建安骨;一身傲骨,青莲居士谪仙人。

”这位既有“千古诗才”又“一身傲骨”的诗人是李白。

D. 《我的叔叔于勒》作者是法国作家莫泊桑,被誉为“短篇小说巨匠”,代表作有《羊脂球》《项链》等。

【答案】 B【解析】【分析】杜甫的《春望》前四句写春日长安凄惨破败的景象,饱含着兴衰感慨;后四句写诗人挂念亲人、心系国事的情怀,充溢着凄苦哀思,表现了诗人爱国之情。

据此,B项的杜甫的《春望》并不是表达了诗人对春天景物的美好感受,处处洋溢着对大好春光的欣赏、赞美之情。

故答案为B。

故答案为: B【点评】本题考查的是对诗词中心思想的理解和把握。

需要先了解每首诗所表达的作者的感情,再进行比较分析。

3.下列对戏剧有关知识的表述不正确的一项是( )A. 戏剧是通过演员表演故事来反映社会生活中种种冲突的艺术。

它是以塑造人物为中心,包括绘画、雕塑、音乐、舞蹈等的综合艺术。

部编初中中考 上学期语文 短语专项训练及解析

一、中考语文专项练习:短语1.选出与“成绩不错”语法结构相同的一项是()A. 冒了严寒B. 豆腐西施C. 选举风波D. 笔画减省【答案】 D【解析】【分析】本题考查学生对汉语语法知识的掌握能力。

语法知识是学好汉语、运用汉语进行表达的基础,对学生辨析病句、仿写句子、改写句子有很大的帮助。

示例中“成绩不错”式“主谓短语”。

A项是“动宾短语”,B项是“偏正短语”,C项是“偏正短语”,D项是“主谓短语”。

故选择D项。

故答案为:D【点评】常见短语类型有:动宾短语、主谓短语、偏正短语、并列短语等,要掌握不同短语类型的特点,注意区别,并在平时的语言运用中正确使用。

2.下列分析有误的一项是()A. 一触到水,我们刚到的客人就会叫起来,似乎他们溅起的水花能抖掉那脆弱的香蒲身上的冬天。

(句中划线词语都是动词)B. 挑拨离间、目眩神迷、有益无损、人情世故。

(四个短语的结构类型一样)C. “四书”之一的《大学》里这样说:一个人教育的出发点是“格物致知。

”(句中标点符号使用正确)D. 一些薄云掠过月亮时,就像丽江古城中,一个银匠,正在擦拭一只硕大的银盘。

(句中运用了比喻的修辞手法。

)【答案】 C【解析】【分析】C.分析有误。

把引号中的句号移至引号外。

即:“格物致知”。

注意“格物致知”做了“是”的宾语。

故答案为: C【点评】本题考查语法知识的把握,注意词性的区分、短语类型的把握、标点符号的运用、修辞方法的区分。

3.下列各项分析错误的一项是()面对那句“人的心灵应该比大地、海洋和天空都更为博大”的名言,人们往往会自惭形秽。

我们难以拥有那样雄浑的襟怀,不知累积至那种广袤,需如何积攒每一粒泥土、每一朵浪花、每一朵云霓?A. 文中“心灵”“广袤”和“比”分别是名词、形容词和介词。

B. 文中“海洋和天空”“更为博大”分别是并列短语和偏正短语。

C. “人们往往会自惭形秽”一句中的主语是“人们”。

D. “每一粒泥土、每一朵浪花、每一朵云霓”中两个“、”应改为“,”。

  1. 1、下载文档前请自行甄别文档内容的完整性,平台不提供额外的编辑、内容补充、找答案等附加服务。
  2. 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
  3. 3、如文档侵犯您的权益,请联系客服反馈,我们会尽快为您处理(人工客服工作时间:9:00-18:30)。


1
t (h) Q (万m3) A B C D 80 40 20 O
a
400
500
600
(第11题图)

中考专项训练——函数图像(提高篇)
1.甲、乙两组工人同时开始加工某种零件,乙组在工作中有一次停产更换设备,更换设备
后,乙组的工作效率是原来的2倍.两组各自加工零件的数量y(件)与时间x(时)之间
的函数图象如图所示.
(1)求甲组加工零件的数量y与时间x之间的函数关系式.
(2)求乙组加工零件总量a的值.
(3)甲、乙两组加工出的零件合在一起装箱,每够300件装一箱,零件装箱的时间忽略
不计,求经过多长时间恰好装满第1箱?再经过多长时间恰好装满第2箱?

2因长期干旱,甲水库蓄水量降到了正常水位的最低值.为灌溉需要,由乙水库向甲水库
匀速供水,20h后,甲水库打开一个排灌闸为农田匀速灌溉,又经过20h,甲水库打开
另一个排灌闸同时灌溉,再经过40h,乙水库停止供水.甲水库每个排泄闸的灌溉速
度相同,图中的折线表示甲水库蓄水量Q (万m3) 与时间t (h) 之间的函数关系.
求:(1)线段BC的函数表达式;
(2)乙水库供水速度和甲水库一个排灌闸的灌溉速度;
(3)乙水库停止供水后,经过多长时间甲水库蓄水量又降到了正常水位的最低值?

2
3.甲船从A港出发顺流匀速驶向B港,行至某处,发现船上一救生圈不知何时落入水中,
立刻原路返回,找到救生圈后,继续顺流驶向B港.乙船从B港出发逆流匀速驶向A
港.已知救生圈漂流的速度和水流速度相同;甲、乙两船在静水中的速度相同.甲、乙两
船到A港的距离y1、y2(km)与行驶时间x(h)之间的函数图象如图所示.
(1)写出乙船在逆流中行驶的速度;
(2)求甲船在逆流中行驶的路程;
(3)求甲船到A港的距离y1与行驶时间x之间的函数关系式;
(4)求救生圈落入水中时,甲船到A港的距离;
(5)求救生圈在水中漂流的路程。

4.甲、乙两地相距720km,一列快车和一列慢车都从甲地驶往乙地,慢车先行驶1h后,快
车才开始行驶,已知快车的速度是120km/h,以快车开始行驶计时,设时间为x(h),两
车之间的距离为y(km),图中的折线是y与x的函数关系的部分图象.根据图象解决下列问
题:
(1)慢车的速度是 km/h,点B的坐标是 .
(2)线段AB所表示的y与x之间的函数关系式是 .
(3)试在图中补全点B以后的图象.

3
5.A、B两地相距630千米,客车、货车分别从A、B两地同时出发,匀速相向行驶.货车
两小时可到达途中C站,客车需9小时到达C站(如图1所示).货车的速度是客车的
3
4
,客、货车到.C.站的距离....分别为y1、y2(千米),它们与行驶时间x(小时)之间的函数

关系如图2所示.
(1)求客、货两车的速度;
(2)求两小时后,货车到C站的距离y2与行驶时间x之间的函数关系式;
(3)如图2,两函数图象交于点E,求E点坐标,并说明它所表示的实际意义.

6.已知:甲、乙两车分别从相距300(km)的M、N两地同时出发相向而行,其中甲到达
N地后立即返回,图1、图2分别是它们离各自出发地的距离y(km)与行驶时间x(h)
之间的函数图象.
(1)试求线段AB所对应的函数关系式,并写出自变量的取值范围;

(2)当它们行驶到与各自出发地距离相等时,用了29(h),求乙车的速度;
(3)在(2)的条件下,求它们在行驶的过程中相遇的时间.

4
图②
图①
DEABCF
7. (本题满分10分)如图①所示,在直角梯形ABCD中,∠BAD=90°,E是直线AB上一点,
过E作直线//BC,交直线CD于点F.将直线向右平移,设平移距离BE为 (t0),直角
梯形ABCD被直线扫过的面积(图中阴影部份)为S,S关于的函数图象如图②所示,
OM为线段,MN为抛物线的一部分,NQ为射线,N点横坐标为4.

(1)梯形上底的长AB= ;
(2) 直角梯形ABCD的面积= ;
(3)写出图②中射线NQ表示的实际意义;
(4) 当42t时,求S关于的函数关系式;
(5)当t为何值时,直线l将直角梯形ABCD分成的两部分面积之比为1: 3.

8.某加油站五月份营销一种油品的销售利润y(万元)与销售量x(万升)之间函数关系
的图象如图中折线所示,该加油站截止到13日调价时的销售利润为4万元,截止至15日
进油时的销售利润为5.5万元.(销售利润=(售价-成本价)×销售量)
请你根据图象及加油站五月份该油品的所有销售记录提供的信息,解答下列问题:
(1)求销售量x为多少时,销售利润为4万元;
(2)分别求出线段AB与BC所对应的函数关系式;
(3)我们把销售每升油所获得的利润称为利润率,那么,在OA、AB、BC三段所表示的销
售信息中,哪一段的利润率最大?

1日:有库存6万升,成
本价4元/升,售价5元/
升.
13日:售价调整为5.5元/
升.
15日:进油4万升,成本
价4.5元/升.

五月份销售记录

相关文档
最新文档