情态动词can,may,must用法

1、情态动词 can的用法 may的用法 must的用法1can的用法1.I can lift the stone.2.You can borrow my bike tomorrow.3.Can it be true? 4.It cant be true. 1.能力 2.许可 3.猜测（用于疑问句、否定句）.can与be able to的区别1.He says he will be able to be home for Christmas.2.I was able to help you yesterday.3.This problem can be settled at once.can有现在

2、时、过去时；可用于被动语态。be able to有各种时态；指某一次动作；不可用于被动语态。2.常用句型 1. could have done 2. can/could have done ? 3. cant/couldnt have done1.She could have explained the matter.2.Can she have told a lie?3. Where can/could he have gone?4.He cant/couldnt have said that.5.She cant/couldnt have been at home all this tim

3、e.本来能够做 可能做过吗？ 不可能做过3may的用法1.You may go home now,Susan.2.You may not smoke in the classroom.3.May I sit down? Certainly./ Yes,please./ Why not?/ Sure. No, I am sorry./ Im afraid you cant.4.I may borrow this book, maynt I?。1.许可表示许可时，无甚区别，may较正式，can较口语化。5.May I speak to you for a moment,professor?6.Ca

4、n I have a cup of tea, mother?42.猜测、可能性（用于肯定句中）1.The story may or may not be true.2.Can that be true? May that be true?3.He cant know the truth. He may not know the truth.他不可能知道真相。 他可能不知道真相。may have done 可能做过1.she may have missed the bus.2.It may have drizzled during the night.5must的用法1.You must get

5、 up much earlier.2.You must not speak ill of others.3.Must we wash the dishes at once/ Yes, you must. No, you neednt ./ you dont have to.4.Our boy must do the opposite to what we ordered.5Just when I was busy , she must come and chatter.6.Its 10 oclock .My mother must be angry.7.We thought our teach

6、er must be joking.。1.必须、一定 2 .偏偏 3.猜测（用于肯定句）6。must have done 肯定做过1.It must have rained last night.The ground is wet.2.No one answers the phone bell.They must have gone out.。构成的反意疑问句1.We must work hard at maths,_ ?2.You must realize that we cant allow such behavior, _ ?3.They must to there at once, _

7、 ?4.The houses must be clean if there are guests, _ ？needntt wemustnt youneednt theyneednt they。必须mustnt/neednt。有必要neednt75.You mustnt talk like that ,_?6.Students mustnt talk during lessons, _ ?7.Mary must be in the room,_ ?8.You must live near my friend if you live in the New Street,_ ?9.Mike must have studied French ,_?10.They must have done their homework yesterday,_