精选优质文档-倾情为你奉上I. 过去完成时/过去完成进行时 练习： 1. He _ more than 5,000 English words when he entered the university at the age of 15. A. has learned B. would have learned C. learned D. had learned 2. They _ on the program for almost one week before I joined them, and now we _ on it as no good results have come out so far. A. had been working; are still working B. had worked; were still C. have been working; have worked D. have worked; are still working 3. Fathe
