TrafficconditionsinBeijing

問題詳情：

 Traffic conditions in Beijing ______ for decades. At first people only complained about jams during rush hours, but today every hour is rush hour.

A. are worsening                                     B. have worsened      

C. have been worsening                                D. have been worsened

【回答】

C

知識點：動詞時態與語態

題型：選擇題