He must have known the truth yesterday, _________?

A. haven’t you       B. didn’t you       C. have you           D. did you

 You’d better not smoke here, ________?

I don't think you have eaten so many crisps ,____?

A. do I    B. haven't you    C. have you     D. don't you

—David has made great progress recently.

—      , and      .

A．So he has; so you have                   B．So he has; so have you

C．So he does; so have you                  D．So has he; so have you

I don’t think you have made great mistakes, _______?

A. do you     B. don’t you        C. have you      D. haven’t you