给你类似的题目参考: The questions are very easy.The children can understand them.(合并为一句) The questions are _easy_ _enough_ for the children to understand. 我怀疑你的选择题就是改自前两句.选项C应该就是正确答案:can 初中题常只有三个选项. The questions are very easy; you _____ answer them. A.could B.should C.can 答:C 译:这些题目很容易,你能回答. 析:should表示“应该”,不合句意. could为can的过去式,可以表示过去的“能力”,也可以表示“虚拟语气”,用在这里不当.所以最佳答案应该就是楼主漏掉的can.