问题

It never _____ humans until the mid
A:occur
B:is occurred
C:occurred to
D:occurred
B:is occurred
C:occurred to
D:occurred
正确答案是:
同类题型
I find it very important to learn English well.— ________. [ ]
The first thing ______ we should do is to tell him the news.
They won’t be back home until the work _____. [ ]
I’m really shy and I just don’t enjoy the party,I don’t know anyone there?[ ]
The mother with her son ________ at home ________ that snowy night.