学习课件

学习单词表，背诵，备测！

虚拟语气:

could have done; would have done;

needn’t have done

should have done; ought to have done;

shouldn’t have done; oughtn’t to have done;

 

肯定推测

must have done(100%); 

could havedone(80%)

may have done; might have done (50-60%)