1.I wish to go home now,___ I A.may B.can't C.must D.do

1.I wish to go home now,___ I A.may B.can't C.must D.do
2.The taxi ___ only hold six passengers.It is full.you take the next one.A.may...may B.can...may C.may...can D.must...can
3.He must have finished his homework,_____he?
A.mustn't B.didn't C.needn't D.hasn't
4.This pen looks like mine,yet it isn't.Whose ____ it be?
A.mnst B.can c.may D.might