Whenthebosscamein,theseworkerspretendedto　　　carefully.A...

問題詳情：

When the boss came in, these workers pretended to　　　

carefully.

A. working                          B. be working

C. work                             D. have been work

ing

【回答】

B

知識點：現在進行時及其被動式

題型：選擇題