英语必修Ⅴ北师大版UNIT13课件（共8张）情态动词表推测用法.ppt

1、情态动词表推测用法(一)情态动词对现在事情进行推测-情态动词+动词原形(do)n Its already 12:30.You must be hungry now.n The light is still on.He must be working in the office now.n must用于肯定句中，表很有把握的肯定推测，译为“一定”。n Jack cant be a policeman,for hes much too short.n Mr.Bush is on time for everything.How can it be that he was late for the o

2、pening ceremony?n can 用于否定句或疑问句中，表很有把握的否定推测，译为“.不可能”/.可能.”n He may be in the classroom.Ill go and make sure.n-Are you coming to the party?-Im not sure.I might go to the concert instead.n may/might 用于肯定句中，语气不很肯定，译为“可能”。(二)情态动词对过去事情的推测-情态动词+have donen I didnt hear the phone.I must have been asleep.n J

3、ack cant have arrived yet;otherwise he would have telephone me.n Sorry Im late.I might have turned off the alarm clock and gone to sleep again.n must have done一定做过n cant/couldnt have done 一定没做过n might/could have done可能做过(三)情态动词表责备语气n We should have studied last night,but we went to the concert inste

4、ad.n I was really anxious about you.You shouldnt have left home without a word.n should/ought to have done-本应该而没做了（表强烈的责备或遗憾的语气）n He might have given you more help,even though he was very busy.n could/might have done-本可以做而没做（责备或遗憾的语气比should/ought to have done 弱）n There was plenty of time.She neednt have hurried.n neednt have done-本不应该做而做了