问题
选择题
In the last ten years, they _______ three great scientific experiments.
A.finished
B.have finished
C.had finished
D.have been finished
答案
答案:B
"in the last / past..." "在过去的......时间里"常用于现在完成时。
In the last ten years, they _______ three great scientific experiments.
A.finished
B.have finished
C.had finished
D.have been finished
答案:B
"in the last / past..." "在过去的......时间里"常用于现在完成时。