必备英语英语现在完成时易错题精选 一、初中英语现在完成时 1．一 How long your brother ______ this camera? — For two weeks. A. have; bought B. have; had C. has; had D. has; bought 【答案】 C 【解析】【分析】本题考查动词的时态。句意：“你哥哥买这个相机多久了?”“两周了。”根据答语“For two weeks. ”可知本句的动词应该使用延续性动词have，不能使用短暂性动词buy。主语是your brother，为第三人称单数，所以应该选择C项。 【点评】考查现在完成时。 2．—How do you like Beijing, Miss Read? —I've no idea. I _____ there. A. have gone B. have been C. haven't been D. haven't gone 【答案】 C 【解析】【分析】句意：---你觉得北京怎么样，瑞得小姐？---我不知道，我没有去过那儿。短语：have been to去过某地（已经返回）；have gone to去了某地（尚未返回），根据句意，故答案为C。 【点评】考查短语辨析，区分have been to与have gone to，理解句子，根据语境判断答案。 3．I scared of dogs ever since a dog hurt me when I was five years old. A. will be B. was C. have been D. would be 【答案】 C 【解析】【分析】由since引导的从句可知主句应用现在完成时，故答案为C。句意是：自从我五岁时被狗伤过之后我就一直怕狗。 【点评】本题考查现在完成时的用法。 4．He ___________ for ten years. A. has been married B. married C. got married D. has married 【答案】A 【解析】【分析】在现在完成时态里，当出现for+段时间时，短暂性动词必须换成延续性动词。get married需换成be married。故选A。 【点评】该题考查的是对现完时态中的短暂性动词与延续性动词动词的掌握，这一块内容是中考的重难点，考试频率占时态考查题的一半以上。学生必须牢记这两种词的转换及转
九年级单项选择专练 C1. --- ____ do you study for a test? --- I study by listening to tapes. A. What B. Which C. How D. Where B2. I _____ really quiet. Now I’m very outgoing. A. use to be B. used to be C. use to D. used to A3. Ann ____ to choose her own clothes, but she isn’t allowed to get her ear pierced穿耳洞yet. A. is allowed B. allow C. allowed D. is allowing D4. ---What ___ you do if you had a million dollars? --- I’d give it to charity. A. will B. did C. were D. Would ①提出将来会发生的事：主句：主语＋would/should/might/could＋动词原形 从句：if+should＋动词原形/were to＋动词原形 eg. If he should go to Harvard University, he would make full use of his time. 如果他要上哈佛大学的话，他就会充分利用他的时间了。 ②提出现在的条件：主句：主语＋would/should/might/could＋动词原形 从句：if+动词过去式 eg. If he studied at this school, he would know the enviornment around the school very much. 如果他在这所学校学习的话，他会很了解周边环境。 ③提出过去的未发生的条件：主句：主语＋would/should/might/could have＋动词过去分词 从句：if+had＋动词过去分词 A5. --- Have you ever ____ another country? ---- Yes, I have. A. been to B. gone to C. be to D. went to B6. --- _____ would you like to go ? --- I’d like to go somewhere warm. A. Which B. where C. What D. How B7. He looks sad. Let’s ____ . A. to cheer him up B. cheer him up C. to cheer up him D. cheer up him C8. ----Jack,you look tired today. What’s wrong?
六安数学三角形填空选择易错题（Word 版 含答案） 一、八年级数学三角形填空题（难） 1．如图，在△ABC 中，∠C =90°，BC =8cm ，AC =6cm ，点E 是BC 的中点，动点P 从A 点出发，先以每秒2cm 的速度沿A →C 运动，然后以1cm /s 的速度沿C →B 运动．若设点P 运动的时间是t 秒，那么当t =___________________，△APE 的面积等于6． 【答案】1.5或5或9 【解析】 【分析】 分为两种情况讨论：当点P 在AC 上时：当点P 在BC 上时，根据三角形的面积公式建立方程求出其解即可． 【详解】 如图1，当点P 在AC 上．∵△ABC 中，∠C =90°，BC =8cm ，AC =6cm ，点E 是BC 的中点，∴CE =4，AP =2t ． ∵△APE 的面积等于6，∴S △APE = 12AP ?CE =12 AP ×4=6．∵AP =3，∴t =1.5． 如图2，当点P 在BC 上．则t ＞3∵E 是DC 的中点，∴BE =CE =4． ∵PE ()43=7-PE t t =-- ，∴S =12EP ?AC =12 ?EP ×6=6，∴EP =2，∴t =5或t =9． 总上所述，当t =1.5或5或9时，△APE 的面积会等于6．故答案为1.5或5或9． 【点睛】 本题考查了直角三角形的性质的运用，三角形的面积公式的运用，解答时灵活运用三角形的面积公式求解是关键． 2．如图，平面内有五个点，以其中任意三个点为顶点画三角形，最多可以画_____个三角形．
【答案】10 【解析】 【分析】 以平面内的五个点为顶点画三角形，根据三角形的定义，我们在平面中依次选取三个点画出图形即可解答. 【详解】 解：如图所示，以其中任意三个点为顶点画三角形，最多可以画10个三角形， 故答案为：10． 【点睛】 本题考查的是几何图形的个数，我们根据三角形的定义，在画图的时候要注意按照一定的顺序，保证不重复不遗漏. 3．如图，已知：四边形ABCD中，对角线BD平分∠ABC，∠ACB＝74°，∠ABC＝46°，且∠BAD+∠CAD＝180°，那么∠BDC的度数为_____． 【答案】30° 【解析】 【分析】 延长BA和BC，过D点作DE⊥BA于E点，过D点作DF⊥BC于F点，根据BD是∠ABC的平分线可得出△BDE≌△BDF，故DE=DF，过D点作DG⊥AC于G点，可得出 △ADE≌△ADG，△CDG≌△CDF，进而得出CD为∠ACF的平分线，得出∠DCA=53°，再根据三角形内角和定理即可得出结论． 【详解】 解：
一般将来时易错题集锦 一、单项选择一般将来时 1．—Your windows are still open? It's so cold! —Oh, sorry. They ________. A．aren't closing B．won't dose C．won't be closed D．aren't closed 【答案】B 【解析】 试题分析：考查close的用法。由题目可知，不是回答者不关窗，而是窗子由于种种原因（窗子坏了）关不了，they指代窗户为主语，因此为主动。Close既可作及物动词，又可作不及物动词，此句中为不及物动词，句意为你的窗户还是开的，真是太冷的。对不起，它们关不了。故选B。 考点：考查close的用法。 2．--I have you asked John to come to the party this evening？ --Yes，I have，but he＿＿＿＿ A．doesn't B．hasn't C．hadn't D．won't 【答案】D 【解析】 试题分析：此处doesn't 表示一般现在时； hasn't 现在完成时；hadn't 过去完成时； won't 一般将来时，意为：不愿，表意愿。句意：—我让你请求John来参加今晚是聚会？—是的，我请了，但他不愿意来。根据句意选D。 考点：考查动词时态。 3．The computers made by our company sell best, but several years ago no one could have imagined the role in the markets that they ________. A．were playing B．were to play C．had played D．played 【答案】B 【解析】 试题分析：考查时态：我们公司生产的电脑卖的最好，但是几年以后没有人能想象它曾经将在市场中扮演什么样重要的角色。were to do是过去将来时，表示过去想象电脑将会起到的作用。选B。 考点：考查时态 4． Turn on CCTV news and we ________how happy our life is. But there is no denying that over the past decades, the cost of living ________ sharply. A．are seeing; had increased B．will see；has been increasing C．see; increased D．have seen; is increasing 【答案】B
中考英语单选各种难题易错题 A. What fine weather B. What a fine weather C. How a fine weather D. How fine a weather 解析：选A. 此题容易误选B. weather是不可数名词，前面不能有不定冠词。英语中经常考查的不可数名词有work, news, adivice, information等。 ( ) 2. Which is the way to the __________? A. shoe factory B. shoes factory C. shoe’s factory D. shoes’ factory 解析：选A. 此题极易误选B, C, D. 英语中名词单数可以修饰名词，如： an apple tree →two apple trees. 但注意 a man teacher→two men teachers。 ( ) 3. This class ________ now. Miss Gao teaches them。 A. are studying B. is studying C. be studying D. studying 解析：选A. 此题容易误选B. class, family, team等单词如果表示整体谓语就用单数，表示个体就用复数，从语境及其后面的代词them可以看出，class表示个体，故选择A。 ( ) 4. We will have a _________ holiday after the exam。 A. two month B. two-month C. two month’s D. two-months 解析：选择B 此题容易误选C, D. 在英语中数词中间用连字符号加名词单数，构成符合名词，在句中只能作定语，如果选择C, 需要把逗号放s后面。 ( ) 5. There is no enough ________ on the corner to put the table。 A. place B. room C. floor D. ground 解析：选B. 此题最容易误选A.。 room在句中是空间而非房间。句意：角落里没有摆桌子的空间了。 ( ) 6. We can have _____ blue sky if we create _____ less polluted world。(苏州2010) A. a; a B. a; the C. the; a D. the; the 解析：选A. 此题容易误选C, D. 根据句意：如果我们创造一个没有污染的世界，那么我们就用一个蓝色的天空。
初中英语一般现在时易错题精选 一、一般现在时 1．His father always ________ that he didn't have a chance ________ his dream. A. regrets; to achieve B. regretted; achieved C. feels thankful; to achieve D. feels thankful; achieved 【答案】 A 【解析】【分析】句意：他父亲总是很遗憾没有机会实现自己的梦想。regret，遗憾，feel thankful，很感谢，根据didn't have a chance可知，是遗憾的语境，描述客观事实是一般现在时，故谓语是regrets，have a chance to do，固定搭配，有机会做某事，故选A。【点评】考查固定搭配，注意一般现在时和have a chance to do的用法。 2．Millions of people _________ the Great wall every year. A. visited B. visit C. will visit D. are vesting 【答案】 B 【解析】【分析】句意：成千万的人每年参观长城。根据every year，可知句子时态为一般现在时，故答案是B。 【点评】考查一般现在时，注意根据时间状语确定句子的时态。 3．Our Geography teacher told us that the Earth ____________ the sun. A. went around B. goes around C. is going around D. was going around 【答案】 B 【解析】【分析】句意：我们的地理老师告诉我们地球绕着太阳转。地球绕着太阳转是客观事实，故用一般现在时，故选B。 【点评】考查宾语从句时态，注意一般现在时的用法。 4．—Let's go fishing if it ____ this weekend. —But nobody knows if it ____. A. is fine; will rain B. will be rain; rains C. will be fine; will rain D. is fine; rains 【答案】 A 【解析】【分析】句意：——如果本周末天晴，我们一起去钓鱼吧。——但是没人知道是否下雨。第一空if引导条件状语从句，条件状语从句遵循主将从现的原则，从句用一般现在时表将来时，故排除BC，第二空前knows后引导宾语从句，描述将来发生的事情，用一般将来时，其结构为will+动词原形，故选A。 【点评】考查动词的时态和形式。注意一般现在时和一般将来时的用法。 5．It that Yu Mei has changed a lot. A. seems B. looks like C. seems like D. seemed 【答案】 A 【解析】【分析】句意：于梅似乎改变了很多。根据has changed，可知现在完成时是对
（易错题精选）初中数学三角形经典测试题及答案 一、选择题 1．如图，在ABC ?中，90C =o ∠，30B ∠=o ，以A 为圆心，任意长为半径画弧分别交 AB 、AC 于点M 和N ，再分别以M 、N 为圆心，大于12 MN 的长为半径画弧，两弧交于点P ，连结AP 并延长交BC 于点D ，则下列说法中正确的个数是（ ） ①AD 是BAC ∠的平分线；②ADC 60∠=o ；③点D 在AB 的垂直平分线上；④:1:3DAC ABC S S ??= A ．1 B ．2 C ．3 D ．4 【答案】D 【解析】 【分析】 根据题干作图方式，可判断AD 是∠CAB 的角平分线，再结合∠B=30°，可推导得到△ABD 是等腰三角形，根据这2个判定可推导题干中的结论. 【详解】 题干中作图方法是构造角平分线，①正确； ∵∠B=30°，∠C=90°，AD 是∠CAB 的角平分线 ∴∠CAD=∠DAB=30° ∴∠ADC=60°，②正确 ∵∠DAB=∠B=30° ∴△ADB 是等腰三角形 ∴点D 在AB 的垂直平分线上，③正确 在Rt △CDA 中，设CD=a ，则AD=2a 在△ADB 中，DB=AD=2a ∵1122DAC S CD AC a CD ?=??=?，13(CD+DB)22 BAC S AC a CD ?=??=? ∴:1:3DAC ABC S S ??=，④正确 故选：D 【点睛】 本题考查角平分线的画法及性质、等腰三角形的性质，解题关键是熟练角平分线的绘制方法.
2．AD 是△ABC 中∠BAC 的平分线，DE ⊥AB 于点E ，DF ⊥AC 交AC 于点F ．S △ABC =7，DE=2，AB=4，则AC 长是（ ） A ．4 B ．3 C ．6 D ．2 【答案】B 【解析】 【分析】 首先由角平分线的性质可知DF=DE=2，然后由S △ABC =S △ABD +S △ACD 及三角形的面积公式得出结果． 【详解】 解：AD 是△ABC 中∠BAC 的平分线， ∠EAD=∠FAD DE ⊥AB 于点E ，DF ⊥AC 交AC 于点F ， ∴DF=DE ， 又∵S △ABC =S △ABD +S △ACD ，DE=2，AB=4， 11742222 AC ∴=??+?? ∴AC=3. 故答案为：B 【点睛】 本题主要考查了角平分线的性质，熟练掌握角平分线的性质、灵活运用所学知识是解题的关键. 3．△ABC 中，∠A ：∠B ：∠C ＝1：2：3，最小边BC ＝4cm ，则最长边AB 的长为( )cm A ．6 B ．8 C 5 D ．5 【答案】B 【解析】 【分析】 根据已知条件结合三角形的内角和定理求出三角形中角的度数，然后根据含30度角的直角三角形的性质进行求解即可. 【详解】 设∠A ＝x ， 则∠B ＝2x ，∠C ＝3x ， 由三角形内角和定理得∠A+∠B+∠C ＝x+2x+3x ＝180°， 解得x ＝30°，
现在完成时易错题专练 Class_____________ Name_____________ Marks___________ 一、短暂性动词转换延续性动词 ①arrive at/in sw.; get to/reach sw.; come/go/move to sw.→be in/at sw. (1) He got to Beijing five minutes ago. He ________ ________ ________ Beijing for ________ ________ . (2) I moved to the USA last year. I ________ ________ ________ the USA since ________ ________. (3) I went home yesterday. I ________ ________ ________ home for ________ ________. (4) They came here last week. They ________ ________ here since ________ ________. ②come/go back, return → be back; come/go out → be out (1) He came out two years ago. He ________ ________ ________ for ________ ________. (2) We return to Fuzhou yesterday. We ________ ________ ________ to Fuzhou since ________. ③become → be (1) I became a teacher in 2000. I ________ ________ a teacher for ________ ________. (2) The river became dirty last year. The river ________ ________ dirty for ________ ________. ④close → be closed; open → be open
中考英语单项选择易错题精选 1.What do you think ______solve the problem ? A .you can do B.can you do C .you can do to D.can you do to 2 .In the past he often made his sister____, but now he is often made ___by his sister. A. to cry; to cry B. cry; cry C .to cry; cry D .cry; to cry 3 .The teacher told us that the sun ____in the east. A .rises B .rose C .raises D .raised 4 .He lives in a village _____there are a lot of trees. A. there B. where C .that D .which 5. He _________ Alice for ten years. A. married to B .has married to C. has married D.has been married to 6 .We need fifteen more people _____our team to do the job. A .but B .except C. as well D .besides 7 .They won`t allow us ________ at this beach. A .swimming B. to swim C .swam D .swim 8 .Is this factory ______you visited last week? A. that B. where C .the one D. in which 9 .The reason ____he was absent from the meeting was ____his car broke down on the way. A .that; because B .why; that C. that; that D. for; that 10 .Is the river_____ through that town very large? A .which flows B. flows C. that flowing D.whose flows 11 .The teacher told me that the students I wanted to see were seen___ football on the playground just now. A .playing B. to be playing C .play D .to play 12. The red rose is the only one _____I real like. A. which B .who C .that D. whom 13 .All the apples _____ fell down were eaten by the pigs. A .those B. which C. what D. that 14 .Don`t forget the day ______you were received into the Youth League. A .when B .that C .at which D .where
一般过去时易错点解析 例1. 用括号内动词的适当形式填空 I went to the supermarket and (buy) some fruit. 解析：很多同学在做本题时，由于没有找到时间状语，因而不知道应该填什么。句中的and连接了两个并列句，前后时态应该一致，前面用了go的过去时went,所以后面buy也应该用过去时bought. 答案：bought 例2. 用括号内动词的适当形式填空。 He always (play) computer games last year. 解析：有些人会把答案写成plays，虽然主语He是单数第三人称，而且句子中出现了always，但是当你读完整个句子就会发现last year，所以应该用过去时played。一般过去时也可以表示过去经常做某事。 答案：played 例3. 用括号内动词的适当形式填空。 Our teacher said that the earth (move) round the sun. 解析：本题是一道难题。本句是含有宾语从句的主从复合句。主句的谓语动词said是say的过去式，有的同学可能会填moved，但是从句the earth moves round the sun(地球绕着太阳转)是客观真理，所以还是要用一般现在时。 答案：moves 例4. 句型转换。 Miss Green taught us English last year．(变一般疑问句) 解析：本题有的同学可能会写成：Did Miss Green taught you English last year?要注意，如果变一般疑问句时提前了Did，则原句中的实意动词要恢复成原形。可记住如下口诀：“见助动，周原形”。 答案：Did Miss Green teach you English last year? 例5. 单项选择。 ( )There a pen and two books on the desk yesterday． A. is B. are C. was D. were 解答：由yesterday可知本题应该选择过去时，可排除A和B。又因为there be
四年级数学三角形考题分析与易错题分析 以盘龙区小学2016学年下学期期末四年级数学试题进行分析：三角形这一单元知识占11%，所考知识点主要有：锐角三角形、直角三角形、钝角三角形，等腰三角形等边三角形的定义，三角形三边的关系，高的做法，会求三角形和多边形的内角和。如： 近三年考题分析 4、请你想办法求出下面这个多边形的内角和。
考查目的：三角形内角和和钝角三角形的特征。 15．画出下面三角形指定边上的高。 考查目的：三角形高的含义，会正确画不同三角形指定底边上的高。 掌握高的方法。 16、等腰三角形的一个内角是60°，其他两个内角各是多少度？这是（）三角形。考查目的：综合三角形内角和、等腰三角形的特点及等边三角形的特点解决问题。
三角形单元检测卷 一、填空（40分） 个钝角三角形，（）个等腰三角形。 7、在一个三角形的三个角中，一个是50度，一个是80度，这个三角形既是（）三角形，又是（）三角形。 二、选择（18分） 1．下面第（）组中的三根小棒不能拼成一个三角形。 2．一个三角形的两边长分别为3 cm和7 cm，则此三角形的第三边的长可能是（）。 A．3 cm B．4 cm C．7 cm 3．下面各组角中，第（）组中的三个角能组成三角形。 A．60°，70°，90° B．50°，50°，50° C．80°，95°，5° 4．钝角三角形的两个锐角之和（）90°。 A．大于 B．小于 C．等于 5、一个等腰三角形中，其中一底角是75度，顶角是（）。 A、75度 B、45度 C、30度 D、60度 6、下面长度的小棒中（单位：cm），能围成三角形的是（）。 A. 3.5、7.5、4 B . 5、2.8、6 C. 10、4.2、5.6 三、判断（8分） 1、一个内角是80度的等腰三角形，一定是一个钝角三角形。（） 2、等腰三角形一定是等边三角形。（） 3、等腰三角形一定是锐角三角形。（）
现在进行时易错题汇总 一、单项选择现在进行时 1．Professor Wang ________in our school till next Sunday． A．will have stayed B．has stayed C．is staying D．stayed 【答案】C 【解析】 本题考查时态。根据句意：王教授将呆在我们学校直到下周日。这里用现在进行时表示将来，故选C。 2．Since the band announced the release of their new album, the phone hasn't stopped ringing. Many fans ________ to ask about the exact time. A．were calling B．had called C．are calling D．call 【答案】C 【解析】 C 考察动词时态。句意：自从那支乐队宣布了要发行新的专辑的消息，电话铃声就不停地响。很多粉丝一直都打电话询问具体的发行时间。根据句中的hasn’t stopped ringing可知询问具体的时间内这件事情现阶段正在发生，应该使用现在进行时。故C正确。 3．Hurry up! Mark and Carol ________ us. A．expect B．are expecting C．have expected D．will expect 【答案】B 【解析】 试题分析：考查动词的时态。催促别人快点，因为Mark和Carol正等着呢，适合用现在进行时。 【名师点睛】英语中的时态主要由动词的形式决定，因此在学习英语时态时，要注意分析动词形式及具体语境，想象在那个特定的时间动作所发生的背景，这个动作是经常性动作、一般性动作、进行性动作、完成性动作还是将要发生的动作。由Hurry up！可以判断这个动作正在发生。 4．Hi, Mike. I’ve to borrow your car this afternoon mine _______ in the garage. A．is repairing B．is being repaired C．has repaired D．has been repaired 【答案】B 【解析】 试题分析：考察时态语态。句义：今天下午我不得不借用你的汽车，因为我的汽车正在修理厂被修理。根据句义可知我的汽车正在被修理是正在发生的事情。根据句义说明B项使用现在进行时的被动语态正确。
最新中考英语语法单项选择易错题精选20题 （附解析） 1.____is well-known that Taiwan is part of China. A. It B. That C. What D. As 2.____ is clear to us all, students should obey the school’s rules. A. As B. What C. Which D. It 3.____ is known to all is that China is a developing country. A. What B. As C. Which D. It 4.Mao Zedong was born in Shaoshan, ____ now is a place of interest. A. which B. as C. it D. that 5.He spent as much time as he could ____ the experiment. A. do B. to do C. did D. doing 6.He did what he could ____ his mother do some housework. A. to do B. do C. did D.doing 7.Stay ____ you are. I’ll be back soon. A. in which B. where C. there D.at the place which
8.He came to the second storey window, ____he could see what was happening across the rive. A. from which B. from it C. which D. from where 9.She is alone at home, so she has no one ____she can turn for help. A. whom B. / C. to who D.to whom 10.____advice will you fellow? A. Whose else B.Who’s else C. Who else’s D. Who’s else’s 11.He came to the shop,_____was tightly closed. A. who’s door B. which door C. its door D. the door of which 12.He was praised____what he did. A. because B. be came of C. for the reason D. as 13.The reason ____he was turned down is ____he had no money. A. why;that B. why;because C. that;why D. that;because 14.He found ____honor to be invited to give a talk here. A. that it an B. that an C. it a D. it was an
初中数学三角形易错题汇编及答案 一、选择题 1．如图，在平面直角坐标系中，已知点A（﹣2，0），B（0，3），以点A为圆心，AB长为半径画弧，交x轴的正半轴于点C，则点C的横坐标介于（） A．0和1之间B．1和2之间C．2和3之间D．3和4之间 【答案】B 【解析】 【分析】 先根据点A，B的坐标求出OA，OB的长度，再根据勾股定理求出AB的长，即可得出OC 的长，再比较无理数的大小确定点C的横坐标介于哪个区间． 【详解】 ∵点A，B的坐标分别为（﹣2，0），（0，3）， ∴OA＝2，OB＝3， 在Rt△AOB中，由勾股定理得：AB22 = 2+313 ∴AC＝AB13， ∴OC132， ∴点C132，0）， <<， ∵3134 <<， ∴11322 即点C的横坐标介于1和2之间， 故选：B． 【点睛】 本题考查了弧与x轴的交点问题，掌握勾股定理、无理数大小比较的方法是解题的关键． 2．等腰三角形两边长分别是 5cm 和 11cm，则这个三角形的周长为（） A．16cm B．21cm 或 27cm C．21cm D．27cm 【答案】D 【解析】 【分析】 分两种情况讨论：当5是腰时或当11是腰时，利用三角形的三边关系进行分析求解即可．
【详解】 解：当5是腰时，则5+5<11，不能组成三角形，应舍去； 当11是腰时，5+11＞11，能组成三角形，则三角形的周长是5+11×2=27cm． 故选D． 【点睛】 本题主要考查了等腰三角形的性质, 三角形三边关系，掌握等腰三角形的性质, 三角形三边关系是解题的关键． 3．下列命题是假命题的是（） A．三角形的外心到三角形的三个顶点的距离相等 B．如果等腰三角形的两边长分别是5和6，那么这个等腰三角形的周长为16 C．将一次函数y＝3x-1的图象向上平移3个单位，所得直线不经过第四象限 D．若关于x的一元一次不等式组 213 x m x -≤ ? ? +> ? 无解，则m的取值范围是1 m￡ 【答案】B 【解析】 【分析】 利用三角形外心的性质、等腰三角形的性质和三角形三边关系定理、一次函数图象的平移规律、解一元一次不等式组分别判断后即可确定正确的选项． 【详解】 A. 三角形的外心到三角形的三个顶点的距离相等，正确，是真命题； B. 如果等腰三角形的两边长分别是5和6，那么这个等腰三角形的周长为16或17，错误，是假命题； C. 将一次函数y＝3x-1的图象向上平移3个单位，所得直线不经过第四象限，正确，是真命题； D. 若关于x的一元一次不等式组 213 x m x -≤ ? ? +> ? 无解，则m的取值范围是1 m￡，正确，是真 命题； 故答案为：B 【点睛】 本题考查了命题与定理的知识，解题的关键是了解三角形外心的性质、等腰三角形的性质和三角形三边关系定理、一次函数图象的平移规律、解一元一次不等式组． 4．如图，在ABC ?中，AB的垂直平分线交BC于D，AC的中垂线交BC于E， 20 DAE ∠=o，则BAC ∠的度数为( )
一般过去时易错题及解析 一、单项选择一般过去时 1．When I was in university, I ______ at a loss what to do in the future for a long time. A．had felt B．have felt C．felt D．would feel 【答案】C 【解析】 【详解】 考查动词时态。句意：当我在大学的时候，我很长一段时间都不知道将来该做什么。结合上文When I was in university可知是发生在大学时候的事情，故用一般过去时。故选C。 2．The young couple _______ as volunteer teachers for a whole year during their stay in Yunnan. A．have worked B．had worked C．worked D．have been working 【答案】C 【解析】 【详解】 考查时态。句意：在云南期间，这对年轻的夫妻做了一整年的志愿者。根据句意可知他们是在云南期间做志愿者的，使用一般过去时描述过去发生的事情，并没有延续到现在，也没有表现出对现在的影响，故C项正确。 3．---- Have you ever been to Provence which is home to lavender(薰衣草) in Paris? ---- Yes, only once. I ________ there for a week. A．had stayed B．were staying C．have stayed D．stayed 【答案】D 【解析】 【详解】 考查时态。句意：—你去过巴黎薰衣草的故乡普罗旺斯吗?—是的,只有一次。我在那里呆了一个星期。此处是指过去发生的一件事，与现在无关，所以用一般过去时态，故答案为D。 4．—How long _____each other before they _____here? —For about a year. A．have they known, come B．did they know, came C．do they know, come D．had they known, came 【答案】D 【解析】 【详解】 考查时态。句意：—他们来这儿之前认识多久了？—大约一年了。根据句意分析，他们来到这里是过去的事，他们互相了解大约一年的时间肯定发生在来这里之前，发生在过去某
九年级中考英语单项选择题易错题专练 1. A. Do you know girl in red ? B. Yes, she’s a professor of university. A. the, a B. the ,the C. a, an D. the, an 2.Tonny is honest man and we all like him. A. a B. an C. the D./ 3.We can have bluer sky if we create less polluted world. A.. the, a B. a ,a C. a, an D. the, an 4. of the land in that district covered with trees and grass. A. Two fifths, is B, Two fifth, are C. Two fifth, is D. Two fifths , are 5.Do you know ? Of course. Food is OK to eat if you pick up as soon as possible. A 5-seconds-rule B. 5-second-rule C. 5-seconds-rulesD. 5-seconds rule 6. We will celebrate my pet dog’s birthday. A .two B. second C. The second D the two 7. A. Did you find the small village yesterday ? B. Yes, without any difficulty, for it has changed over the years. A. hardly B. greatly C. clearly D. nearly 8.A. What was weather like yesterday afternoon ? B. It was terrible. It rained . We could go out. A. hard, hard B. hardly, hardly C. hard, hardly D. hardly, hard 9.Thanks to man-made satellites, the world itself is becoming a smaller place. A. more B. most C. much D. much more 10. The we do for the people, the we will be. A. much, happy B. more, happier C. little, happy D. least, happiest 11.Many Chinese students think science subjects are foreign language learning. A. more difficult as B. less difficult than C. much difficult D. so difficult as 12.David jumped in the long jump. He won the game! A. longest B. farthest C. fastest D. highest 13. A. What do you think of the lecture of Li Yang’s Crazy English ? B. I think it’s , but someone think it’s much too . A. wonderful enough, bored B enough wonderful, boring C. wonderful enough, boring D. enough wonderful, bored 14. A. What made you so ? B. The noise upstairs. A. angrily B. angry C. happy D. happily 15.The old woman lives , but she never feels . A. lonely, alone B. alone, lonely C. lonely, lonely D. alone, alone 16. He’s wearing a pair sunglasses to protect his eyes the strong sunlight. A. from B in C. to D. with 17.We can see a full moon the evening of August the 15th every years. A. in B. on C. to D. at 18. Boys and girls , wish you to do well in the English exam a light heart. Good luck to everyone ! A. on B. with C. without D. about 19. I usually go to school bike, sometimes I go to school foot. A. with, on B. on, by C. on, with D. by, on 20.A. Can you speak Chinese or Japanese ? B. I can speak , but I can speak English. A. both B. either C. all D. neither 21. My son wants a pet rabbit for long, but I have no time to buy for him. A. it B. one C. the one D.that 22.The shoes don’t fit me.Would you please show me ? A.the other one B.the others C.another pair D.another one 23. A. Is that dog ? B. No. is white. A. hers, His B. him, His C. he , His D. her, Hers 24. I don’t have to tell you. A. something new B. new something C. anything new D. new anything 25. Maybe the disaster can destroy our homes, but can destroy the love in our people. A. everything B. nothing C. something D. anything 26. Help to some fish, children. A. yourself B. ourselves C. myself D. yourselves 27. A. the soldier are very tired, they keep on working. B. They are great. We must learn from them. A. Because, / B. Though, / C. Because, so D. Though, but 28. A good friend always gives you a helping hand you’re in trouble. A. when B. before C. until D. though 29.I gave you a map you woulfn’t get lost. A.if B.because C.so D.that 30.It is said that we have to put off the camping the bad weather. A.because of B.because C.so D.like 31.We will go for a picnic it doesn’t rain this Sunday.