----Whydoesthelakesmellterrible? ----Becauselargequant...

問題詳情：

 ---- Why does the lake smell terrible?

 ---- Because large quantities of water ____________.

       polluted             B. is being polluted       

      C. have been polluted        D. has been polluted 

【回答】

C

知識點：現在完成時及其被動式

題型：選擇題