—Hey,man.Youcan’tcrossthestreetnow.Youhavetowait

問題詳情：

—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

【回答】

C

知識點：連詞

題型：選擇題