Question

—Hey, man. You can’t cross the street now. You have to wait ______ the traffic turn green.
—Oh, sorry and thank you.

A．when

B．after

C．until

D．while

Answer 1

C

A项在……的时候；B项在……之后；C项到……为止，在……以前；D项当……的时候。句意“嘿，伙计。现在你不能穿过街道。在交通灯变绿以前，你必须等。C项符合题意。