Question

The children were worried about their mother. They didn’t go to bed ___  their mother came back..

A．when

B．while

C．until

D．a(chǎn)fter

Answer 1

C

解析試題分析：句意：孩子們擔(dān)心他們的媽媽，直到媽媽回來后他們才上床睡覺。not…until…直到……時候才……。故選C。
考點：考查連詞。