1.He knew she was wrong,but he ____ tell her.
A.dared not to B.dared not C.doesn't dare D.doesn't dare to
此题答案为B.dare作为情态动词不加to,作为行为动词才加to.
2.There are so many spelling mistakes in your translation.You ____ more careful.
A.must be B.must have been C.ought to be D.ought to have been
此题答案为D.ought to have been = should have been 含“责备”语气.
3.They are all busy .I ___ go there alone.
A.can but B.cannot but C.may but D.mat not but
此题答案为B.cannot but "不得不"
4.---Could I call you by your first name?
---Yes,you___.
A.will B.could C.may D.might
此题答案为C.you may “你可以”.B改为can也对.
5.We have spent much longer time than expected.We ___ the wrong road.
A.took B.must be taking C.were taking D.must take
此题答案为A.took过去时,陈述过去的动作.
6.Such a small child as you ____ a ticket.
A.needn't B.dont't need C.doesn't need D.needn't to have
此题答案为C.本句主语为a small child ,第三人称单数.