问题
It was not until the beginning of the twentieth century_______ to explore space. [ ]
A: did man begin
B: when man began
C: that man began
D: then man began
B: when man began
C: that man began
D: then man began
正确答案是：
同类题型
Hi,Tracy,you look tired. -I am tired.I____ the living room all day. [ ]
Whether people are rich or poor, they are all ____ before the law. [ ]
Give me another chance, ______ I’ll give you all a wonderful surprise.
Sunshine cinema _____________a film called Love boat.
The food here is so bad that every other restaurant in the world must be ____ this one.