Question

—Why do you look so tired?—Because we ________ for three hours without stopping. A．work B．

—Why do you look so tired?—Because we ________ for three hours without stopping. A．work B．worked C．have worked D．were working

Answer 1

C

试题分析：句意:-为什么你们看起来这么疲惫？-因为我们已经不停地工作了三个小时了。work是一个动词，意思是工作。根据句意可知，说话人已经工作了三个小时了，表示从三个小时之前就工作，一直持续到现在，故应该用现在完成时，故选C。A是一般现在时；B是一般过去时；D是过去进行时。