【正文】
up at five (but in fact you went to bed again then).“needn’t+完成式”表示“本來(lái)沒(méi)有必要做某事,而實(shí)際上卻做了”。He could speak English at 。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。2. mustn’t意為“禁止、不許”,用來(lái)表達(dá)命令,表示強(qiáng)烈的語(yǔ)氣。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)?lái)。A knife can be used for cutting things.(刀可以用來(lái)割東西)/ A knife can be used to cut things.(刀可以用來(lái)割東西)。I haven’t got any money with me, so I’ll have to borrow some from my friend.我身上沒(méi)帶錢(qián),只好向朋友借點(diǎn)了。(3)否定句中表示推測(cè)。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(wèn)句中表示推測(cè)用can,不用might,may,must3) 在否定句中用can’t(不可能),不用may,must。另外be able to常常指經(jīng)過(guò)努力,花費(fèi)了時(shí)間和勞力之后才能做到某事。如:She must have seen the film before,hasn’t she?(注意反意疑問(wèn)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(wèn)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(méi)有做”;“shouldn’t+完成式”表示“本來(lái)不應(yīng)當(dāng)做,而實(shí)際上卻做了”??键c(diǎn)五:情態(tài)動(dòng)詞表示推測(cè)的用法:一、“情態(tài)動(dòng)詞+動(dòng)詞原形”表示對(duì)現(xiàn)在的推測(cè)。5. shouldn’t表示不應(yīng)該。He mustn’t leave his 。(2)當(dāng)句子表推測(cè)時(shí),用can’t表達(dá)不可能,He can’t be ill. He is playing chess with ,他正和Tom下棋呢。ll stay with you and help you.10. had better的用法:had better意為“最好”,沒(méi)有人稱的變化,后面接不帶to的不定式,其否定形式為:had better not。You should have finished your ?!癢hy not...?”實(shí)際上是“Why don39。注意:在口語(yǔ)中,dare的各種形式常與不帶to的不定式連用。I need to do it right 。 (4) must表示有把握的推測(cè),用于肯定句。He is away from school. He might be ,可能是他生病了。(2). could在疑問(wèn)句中,表示委婉的語(yǔ)氣,此時(shí)could沒(méi)有過(guò)去式的意思。I can see with my 。She can swim fast, but I can’t . 她能游得很快,但我不能。He could write poems when he was 10. 他十歲時(shí)就會(huì)寫(xiě)詩(shī)。可能性低于may。(3)對(duì)must引導(dǎo)的疑問(wèn)句, 肯定回答為must,否定回答為needn’t 或don’t have to —Must I finish my homework ? 我現(xiàn)在必須完成作業(yè)嗎?—No, you needn’,你不必。(2).need還可以作實(shí)義動(dòng)詞,此時(shí)有人稱、數(shù)和時(shí)態(tài)的變化,如果是人作主語(yǔ)后邊多接動(dòng)詞不定式。He doesn’t dare to break his 。What about/How about a drink? What about/How about taking Tom with us?(3).用“Why not...?”來(lái)提出建議,表示“何不……”not面后接動(dòng)詞原形。(2)Should have done表示對(duì)過(guò)去動(dòng)作的責(zé)備、批評(píng)。He is seriously ill. He is going to die. He will be twenty years old.③. be going to含有“計(jì)劃,準(zhǔn)備”的意思,而will則沒(méi)有這個(gè)意思,She is going to lend us her book.He will be here in half an hour.④.在有條件從句的主句中,一般不用be going to,而多用will, If any beasts es at you, I39。答案:B考點(diǎn)三:不同情態(tài)動(dòng)詞的否定意義也不同:1.(1).can’