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．a(chǎn)fter

C．until

D．while

Answer 1

C

A項在……的時候；B項在……之后；C項到……為止，在……以前；D項當(dāng)……的時候。句意“嘿，伙計�，F(xiàn)在你不能穿過街道。在交通燈變綠以前，你必須等。C項符合題意。