题目内容
Since the 1980s, it ______ possible to listen to British and American English at the flick of a switch.
| A. is | B. has been |
| C. had been | D. was |
B
解析:
略
练习册系列答案
相关题目
My colleague has been recovering gradually since the operation, and it wont’ be long ______ he comes back to work.
|
A.before |
B.since |
C.after |
D.when |