第14题: [单项选择]He won the scholarship. He ______ hard these terms. A. should have worked B. must have worked C. must have been working D. could have worked 参考答案:C 答案解析:本题考查的是情态动词表示推测的情况。Must表示肯定推测,+现在时表示对现在的肯定推测;+完成时则表示对过去情况的肯定推测。同样,+现在完成进行时,则表示对一直以来情况的推测。根据题意,是说他一定这些