初中英語情態(tài)動詞專項(xiàng)講解(參考版)
2025-04-06 23:52本頁面
【正文】 A knife can be used for cutting things.(刀可以用來割東西)/ A knife can be used to cut things.(刀可以用來割東西)。She is used to eating 。易混點(diǎn)六: used to do / be used to doing / be used to do…/ be used for doing sthused to do表示過去常常發(fā)生的動作，強(qiáng)調(diào)過去，只用于過去，注意用to do，不用doing形式；be used to doing意為“習(xí)慣做…”，be可有各種時(shí)態(tài)；be used to do意為“……被使用去做……,”為被動語態(tài)形式。3. have to可以用于多種時(shí)態(tài)；而must只用于一般現(xiàn)在或?qū)?。I haven’t got any money with me, so I’ll have to borrow some from my friend.我身上沒帶錢，只好向朋友借點(diǎn)了。如：I know I must study ?！ ∫谆禳c(diǎn)五：must和have to 。2. mustn’t意為“禁止、不許”，用來表達(dá)命令，表示強(qiáng)烈的語氣。（3）否定句中表示推測。（2）不能。易混點(diǎn)四：can’t和mustn’t1. can’t根據(jù)其基本用法可譯為：（1）不會。Where can they be now? 他們現(xiàn)在可能在哪兒？ That can’t be true. 那不可能是真的。如：Can/ May I help you ? 我能幫助你嗎？ 2. can和may表示可能性時(shí)的區(qū)別：1)在肯定句中用might，may，must，不用can2)在疑問句中表示推測用can，不用might，may，must3) 在否定句中用can’t（不可能），不用may，must。We were able to reach the top of the mountain at 。He has been able to 。He could speak English at 。另外be able to常常指經(jīng)過努力，花費(fèi)了時(shí)間和勞力之后才能做到某事。You could have stayed with the Smiths while you were in New York (but in fact you stayed in a nearby hotel .) Could Mr Li have helped this girl student?“may/might+完成式”表示“過去可能，本來可以于某事而實(shí)際上沒有干”，might的可能性較小，語氣較弱。I saw him just now. He can’t have gone to Japan.She said the man couldn’t have stolen her car.“could +have done/been”表示“過去本來能夠，可以做某事或成為某種狀態(tài)，而實(shí)際上沒有”，說話者有些遺憾。You should have finished your homework earlier (but in fact you did not finish it on time).You shouldn’t have gone to bed when you woke up at five (but in fact you went to bed again then).“needn’t+完成式”表示“本來沒有必要做某事，而實(shí)際上卻做了”。如：She must have seen the film before，hasn’t she?(注意反意疑問句的后半部分)You must have met uncle Wang in the shop yesterday，didn’t you? (注意反意疑問句的后半部分)“should +have done /been”表示“本應(yīng)當(dāng)做某事，而實(shí)際上并沒有做”；“shouldn’t+完成式”表示“本來不應(yīng)當(dāng)做，而實(shí)際上卻做了”。It is already 10 o’clock now they should be there.二、情態(tài)動詞表示對過去可能發(fā)生的動作或存在過的動作的推測性用法。The man may be the headmaster.—Where is Mr Li?—He might be working in his office. —May Mr Li e?—He might not e here.Could表示推測時(shí)，語氣can比要弱，說話者留有余地。That man can＇t be her husband she is still single.Who is knocking at the door? Can it be the postman?must
外語相關(guān)推薦
鄂ICP備17016276號-1