You ________ phonehim if you want to but you ________ ! He is sure to phone you.

You ________ phonehim if you want to but you ________ ! He is sure to phone you.

A.may ...mustn’t

B.have to... needn’t

C.can ...doesn’t need

D.can ...needn’t

答案及解析： D

解析：

译文：如果你想的话，你可以打电话给他，但是你不必那么做，他一定会打给你的。选项D符合。