1、Mary can speak three languages.(知识) Can you skate?(技能) 此时可用be able to代替,can只有一般现在时和一般过去式;而be able to则有更多的时态。 Ill not be able to come this afternoon. 2) 表示请求和允许,常在口语中。-Can I go now?- Yes, you can. / No, you cant. 此时可与may互换。在疑问句中还可用could, might代替,不是过去式,只是语气更委婉,不能用于肯定句和答语中。- Could I come to see you tom
2、orrow?- Yes, you can. ( No, Im afraid not. ) 3) 表示客观可能性(客观原因形成的能力)。Theyve changed the timetable, so we can go by bus instead. This hall can hold 500 people at least. 4) 表示推测(惊讶、怀疑、不相信的态度,用于疑问句、否定句和感叹句中。此时cant译为“不可能”。Can this be true?This cant be done by him. He was able to go to the party yesterday
3、evening in spite of the heavy rain.Can it be our teacher?那个人有可能是我们老师吗?No, it cant be our teacher. He is on a visit to the Great Wall.不可能。咱们老师正在游览长城呢。【例题】I think Miss Gao must be in the library. She said she would go there.No. She _be there, I have just been there.A. cant B. mustnt C. neednt D. would
4、nt【解析】根据下文“我刚去过那儿”可知,应为“不可能”,cant表示推测答案 A对比:be able to 当表示“经过努力才得以做成功某事”时应用be able to,不能用Can。两者表示能力时用法相同,但can只有原形“can”和过去式“could”两种形式,在其他时态中要用be able to来表示。另外be able to常常指经过努力,花费了时间和劳力之后才能做到某事。He has been able to drive.他已经会开车了。Im sure youll be able to finish it quickly.我相信你能迅速地完成。We were able to rea
5、ch the top of the mountain at noon.我们能在中午到达山顶。2. could的用法:(1)can的过去式,意为“能、会”,表示过去的能力。如:He could write poems when he was 10. 他十岁时就会写诗。(2)could在疑问句中,表示委婉的语气,此时could没有过去式的意思。如: Could you do me a favour? 你能帮我个忙吗? -Could I use your pen? 我能用一下你的钢笔吗? -Yes, you can. 可以。1.-_ you help me answer the telephone?
6、-OK.A.Can B.May C.Need D.Must2. Tom is young but he _ fly a kite by himself.can B.mayC.need D.3. Listen! Is that Kate playing the piano in the room?-No. It_ be Kate. She has gone to London.A.may not B.needntC.mustnt D.cant4. -Could I cross the street here?-Of course you _.A. could B. can C. are able
7、 to D. will5. -Mum , _ I play computer games?-Yes, you can, but you have to finish your home work first.would B. must C. may D. need3. may的用法:(1).表示请求、许可,比can正式。May I borrow your bike?我可以借你的自行车吗?You may go home now.现在你可以回家了。(2) 表示推测,谈论可能性,意为“可能,或许”,一般用于肯定句中。It may rain tomorrow .明天可能会下雨。She may be a
8、t home.她可能在家呢.(3) may的过去式为might,表示推测时。可能性低于may。He is away from school. He might be sick.他离开学校了,可能是他生病了。(4) 表示希望、祈求、祝愿,常可译为“祝愿”。通常是用may +主+V例如:May you have a good time.祝你过得愉快。May you be happy!祝你幸福!May you succeed!祝你成功! may be和maybe 用法区别 常用位置may be may为情态动词,be为动词原形 句中,作谓语maybe 副词,大概、也许,相当于perhaps 句首,作
9、状语He may be wrong , but Im not sure.也许他错了,但我也不确定。【例题】_ I borrow your MP3?Sure . Here you are. A. May B. Should C. Must D. Would【解析】在此处表示请求,意为“做可以吗”。答案:A1. She _ know the answer, but Im not sure.A. maybe B. may be C. may D. must2. -Tom, dont drive too fast, you _ hit the others cars. must B. need C.
10、may D. have to4. must的用法:(1).must表示主观看法,意为“必须、一定”。You must stay here until I come back.在我回来之前你必须呆在这儿。Must I hand in my homework right now?我必须现在交作业吗?(2)must表示有把握的推测,(只用于肯定的陈述句)。 The light is on, so he must be at home now.灯亮着,他现在肯定在家。Youre Toms good friend, so you must know what he likes best.(3)其否定形式
11、mustnt 表示“一定不要”“千万别”“禁止, 不许”。You mustnt play with fire. 你不许玩火。You mustnt be late. 你一定不要迟到。(4)对must引导的疑问句,肯定回答为must, 否定回答为neednt 或 dont have to . -Must I finish my homework? 我现在必须完成作业吗?-No, you neednt. 不,你不必。对比 have to must是说话人的主观看法, 而have to则强调客观需要。Must只有一般现在时, have to 有更多的时态形式。 The play isnt intere
12、sting, I really must go now. I had to work when I was your age. My brother was very ill, so I had to call the doctor in the mid-night. 我弟弟病得厉害,我只得半夜里把医生请来。 I havent got any money with me, so Ill have to borrow some from my friend. 我身上没带钱,只好向朋友借点了。1.Cars and buses _ stop when the traffic lights turn
13、red. A. can B. need D. must2.-_ we attend the party? -No, you neednt. You are free.Must B. Can C. May D. Shall3. -Must I hand in all my money , Mum?-No, you _ . You can use it to buy some school things. A. mustnt B. cant D. should4.You _ be tired after walking such a long way. Do sit down and have a rest. A. can B.
copyright@ 2008-2022 冰豆网网站版权所有
经营许可证编号:鄂ICP备2022015515号-1