高中英语情态动词PPT课件.pptx

Unit1 Grammar and Usage;一.What are modal verbs?;二. We use modal verbs to talk about:;.We also use modal verbs to:;1.Ability(能力）——can/could:;can/could:;can/could:;can/could:;Attention:;2.Obligation(义务）;have to;;3Certainty(可能性）:;must 表示肯定的猜测，译为“一定”，只能用于肯定句,在疑问句和否定句中表推测时分别要用can/could和cant/couldnt。 This must be your pen. He must be doing his homework now. He cant be in the classroom, for the light has been turned off.;must;;4.Permission(允许）may/might:;may/might:;;5.Making requests (提出要求):;will/would:;will/would:;will/would:;6.Making suggestions (提出建议): Shall(可以）/should(应该） 、Ought to (应该）/had better（最好);shall:;shall:;should:;should:;3. should表示意外或惊讶 常译为 “居然，竟然”。 I can’t believe such a gentleman should be so rude to the old. 我不敢相信这样一个绅士居然对老人如此无礼。 ;4. should 表示猜测时，一般指按经验或逻辑判断，翻译成“照说应该，估计，想必” ;7.Making offers (提供帮助):;三、情态动词+不定式完成式是历年高考的热点之一，可表示“推测”、“责备”、“怀疑”等多种意义。 1. must have done 肯定做了 2. may/might have done 可能已做了 3. can’t/ couldn’t have done不可能做了 4. should /ought to have done本该做但没做 5. shoudn’t/oughtn’t to have done本不该做但做了 6. could have done 本可以做但没做 7.needn’t have done 本不必做但做了 8. would rather have done 本想做但没做;;四. 可兼做行为动词的情态动词：need 、 dare ;;Homework;Thank you!