问题
As we know, you won’t go back to the USA since you have established a research center here．But how long _____ in America? —– For almost
A:did you study
B:have you studied
C:were you studying
D:have you been studying
B:have you studied
C:were you studying
D:have you been studying
正确答案是：
同类题型
I am happy. I just heard I passed my physics exam.—- ________! I’m glad somebody’s happy.
I usually get home late because there is ______ traffic on the road.
_________ homework, most students do it every day. [ ]
________ is Women’s Day？–It’s March 8th.
Dear students, please read every sentence carefully. ______you are, ______mistakes you’ll make.