they don't know what ————yesterdayA.did he happen B.he happened C.happened to him D.was happened to him

问题描述:

they don't know what ————yesterday
A.did he happen B.he happened C.happened to him
D.was happened to him

C,他们不知道昨天他怎么了,他发生了什么事
happen to sb表示某人身上发生了什么事

c

c
happen的主语是事,故A,B都错了;happen 没有被动语态,D错.