问题补充:
By the end of last year, another new gymnasiumin Beijing.
A. would be completed
B. was being completed
C. has been completed
D. had been completed
答案:
A. would be completed
B. was being completed
C. has been completed
(答案→)D. had been completed
解析:考察时态。By与完成时连用,本题by后面的是过去时的时间状语,故使用过去完成时,故D正确。