1、1情态动词讲与练情态动词一情态动词 can_ cant_ May_ may not_Must_ mustnt_ 二、情态动词的特点1. 情态动词无人称和数的变化, 2. 情态动词后面跟的动词需用原形,否定式构成是在情态动词后面加 “not“。 3. 个别情态动词有过去式, 过去式用来表达更客气, 委婉的语气, 时态性不强, 可用于过去，现在。三、情态动词的用法1. can/could； cant/couldnt (否定)1) 表示能力, 意为“能、会”, 例如：I can speak a little English. - Can you ride a bike?I cant swim. -
2、Yes, I can. / No, I cant.2) 表示请求或允许，多用于口语中，意为“可以、能”等You can go home now. 现在你可以回家了 - Can I borrow your bike?You cant stop your car here. - Yes, you can. / No, you cant.3) 用于否定句、疑问句中，表示猜测、怀疑或不肯定.Lucy cant be at home now, she went to the park just now.Where can it be? I cant find my football.【注意：】1）. c
3、ould 是 can 的过去式, 有两种用法, 一种表示过去式；一种用来表达更加客气, 委婉的语气, 时态性不强, 可用于过去，现在。22）. be able to 意为“有能力，能够做.”, 相当于 can/could, 但它有人称，数和时态的变化。2. may; may not (否定)1) 表示“请求，许可” ，此时与 can 同义，可以互换使用May I borrow your bike? Can I borrow your bike?Yes, you may. / No, you may not. Yes, you can. / No, you cant.2) may/might 表
4、示不太肯定的猜测，意为“有可能”Lucy may come to school late today.It might rain today.【注意】：might 是 may 的过去式, 有两种用法, 一种表示过去式，一种表示更加委婉, 客气的语气或对可能性的怀疑。3. must; mustnt (否定)1) must(“必须”, 表示命令)，mustnt(“一定不能”, 表示强烈禁止.) You must go to bed before 22:00pm.You mustnt play with fire. Its dangerous!-Must I write down the sente
5、nces？ -No，you neednt. (-No,you dont have to) 注意：在回答 must 的疑问句中，否定回答用 neednt 或 dont have to 表示“不必” ，不用 mustnt2) must 还可以表示非常肯定的猜测，意为“一定”The girl in a red skirt must be Lucy. 3) must/ have to 的区别：. must 表示必须，强调主观上的愿望；have to 表示“不得不” ，强调客观需要You must go be bed before 22:00pm.My bike is broken, so I have
6、 to go to school on foot. have to 有人称、数、时态的变化；must 则没有。I have to clean the classroom today.3She has to finish her homework first.It was late, he had to go to school without breakfast.【习题】1. -Must I finish the work today? -No,you . You can finish it tomorrow. A. mustnt B. cant C. shouldnt D. neednt 2
7、. - I swim here? -Im sorry. Children swim alone here. A. Must cant B. May must C. Can mustnt D. Cant can 3. -Meng Fei broke his arm while recording If You Are The One in Beijing. -Really? Then perhaps he host TV programmes for some time. A. neednt B. mustnt C. shouldnt D.cant 4. -What do you want to
8、 eat for lunch? I will prepare earlier today. -Honey, you . Lets go out to have something different. A. mustnt B. cant C. shouldnt D.dont have to 5. Thomas, please be quiet. The others hear very well. A. cant B. mustnt C. shouldnt D.neednt 6. -You see, a man is cutting a tree on the Moon. -It be tru
9、e. The teacher says there is no air on the moon. A. cant B.may not C. shouldnt D.mustnt 7. -Can I go fishing with you,Dad? -No, you . You stay at home and do your homework first. A. wont may B. cant must C. shouldnt ought D. neednt should 8. Anna hasnt come to school today. I think she be ill. A. ca
10、n B.has to C. may D.should 9. -Fifty dollars for such a T-shirt! You be joking! -Im serous. Its made of silk. A. must B.need C. may D.can10. _ _I go and apologize to my teacher for my mistake? A. Should B.Need C.Can D. May 11. May I stop my car here,sir? -No,you_. 4A.may not B.mustnt C.cant D.neednt
11、 12. _I change the bulb(灯泡) now? -No,you may not. You_switch off the electricity. A.Can;need B.May;must C.Must;must D.Can;must 13. John_ come to see us tonight, but he isnt very sure yet. A.may B.can C.has to D.must 14. My mother is ill.So I _to look after my little brother. A.must B.may C.have to D
12、.should 15. Im afraid it _rain tonight. A.can B.could C.may be D.might情态动词（should ought to）一、had better 的用法1. had better 是固定词组，意思是“应该；最好” ，后接不带 to 的不定式，其用法相当于情态动词，动词 had 没有人称或数的变化。1) Youd better go there by bus.你最好是坐公共汽车去那里。2) Wed better not tell him the news.我门最好不要告诉他这个消息。二、should 的用法1.情态动词 should
13、常用来表示劝告、建议或义务，意思是“应该” ，：1）You shouldnt come to such a decision hastily .你不应该匆忙作出这样的决定。2）The party should be great fun .那个集会一定很有意思。1. Youd better _ late next time .A. dont B. not be C. not being D. wont be2. - Can I leave this door open at night ?- You _ better not .A. should B. would C. could D. had
14、53. - Lets go to the cinema , shall we ?- _ .A. Yes , I shall B. No , I cant C. Yes , thank you D. No , wed better not7b7 祈使句1.祈使句的定义及句式特征：定义：祈使句是用来表示请求、命令、叮嘱、邀请、劝告或祝愿等的句子。它的特点是通常省略主语 you,以动词原形开头，末尾可用句号或感叹号。祈使句没有疑问句的形式，一般只有肯定和否定两种形式。Go and wash your hands. (表命令)Be quite, please. （Please be quiet.）（表
15、请求）Be kind to your sister.（表劝告）Watch your steps.（表警告）be+形容词 / 名词Be quiet / quick! Be a good student!2）以实义动词开头的祈使句，这种祈使句的常用结构为：动词原形+宾语（+其他）。Come in, please！ Please open your books！3)let 型（Let+宾语+动词原形+其他）Let him do it by himself. Let me help you.3.否定形式（一般在动词上否定，也可以用否定副词（never）来表示）1）be 型【Dont be +其他成分（
16、形容词、名词或介词短语）】Dont be careless! Never be late again next time!在这种句型中，be 不能省略 否定副词 not 不可置于 be 之后2）do 型（Dont +动词原形+其他）Dont believe him! Dont worry! Never do it again!一、单项选择：1. Please _, theyre having a meeting.A. not be so noisy B. be quite C. mustnt talk D. no speaking62. _ to meet me at the station.
17、 Ill be waiting there.A. Not to forget B. Not forget C. Forget not D. Dont forget 3. Its a fine day. Lets go fishing, _?A. wont we B. will you C. dont we D. shall we4. Dont smoke in the meeting-room, _?A. do you B. will you C. can you D. could you5. _ me go. It is very important for me.A. Do let B.
18、Let do C. Doing let D. To do let6. He is not honest. _ believe him. A. Not B. Dont C. To not D. Not to7. _ up early tomorrow, or you cant catch the train.A. Getting B. Get C. To get D. Got8. _ in the street. Its dangerous.A. Not play B. Not to play C. Dont play D. Dont to play9. Lucy, _ the door or
19、someone will come in.A. close B. closes C. not close D. is closing10. _ and play football in the street after lunch.A. Lets not to go B. Lets not go C. Lets dont go D. Not lets go11. A sign with the words“_” is often found in a bus.A. Not parking B. Not smoking C. No parking D. No smoking12. _ Chine
20、se in you English class.A. Not speak B. Dont speak C. Speak not D. Dont speaking13 . _ the boxes. You may use them later. A. Keep B. Keeping C. To keep D. Kept14. Never come late again, _? A. will you B. wont you C. do you D. does he15. The TV is too loud. Please_.A. turn it down B. to turn it down
21、C. turn down it D. to turn down it16. _ cross the road until the traffic lights turns green.7A. Not B. Wont C. Doesnt D. Dont17. Kate, _ your homework here tomorrow.A. bring B. brings C. to bring D. bringing18. _ me the truth, or Ill be angry.A. Telling B. To tell C. Told D. Tell二. 用括号内所给动词的适当形式填空：1
22、. Its an important meeting. _ (not, be )late.2. _ (not,make) any noise! Your mother is sleeping.3. _ (not, speak) with your mouth full of food and _ (be) polite.4. _ ( not, talk) and _ (read) aloud.5. _ (not,leave) your homework for tomorrow, Larry.6. _ (look) out! A car is coming.7. _ (give) us ten years and just see what our country will be like.8. _ (not, let) the baby cry.9. Wear more clothes or you _ (catch) a cold.10. Lets _ (not, say) anything about it.
