（十二）情态动词（表推测用法）
1．I ________have been more than six years old when the accident happened.
A. shouldn' t B. couldn ' t
C. mustn' t D. needn' t
2. He have completed his homework ; otherwise, he wouldn' t be enjoying himself on the play ground..
A. should B. must C. wouldn' t D. can' t
3.—Do you know where David is? I couldn't find him anywhere.
—Well. He have gone far.
— His coat's still here.
A. shouldn' t B. mustn' t C. can' t D. wouldn' t
4.—He stayed in Africa visiting wild animals for seven days.
