Question

【题目】The policeman asked the child ____ cross the street ____ the traffic lights turned green.

A. not, when B. not to, until C. didn't, before D. not to, after

Answer 1

【答案】B

【解析】

试题when当……时；until直到……才；before在……之前；after在……之后。句意：警察要求孩子们直到绿灯亮时，才能通过马路。Not……until直到……才，故选B。