Question

—Has David finished his project yet?
—I guess not. He       on it at lunchtime. Do you want me to confirm it?

A．is working	B．was working
C．has worked	D．had worked

Answer 1

B

解析试题分析：句意：--大卫还没有完成作业吗?—我想没有完成吧，他在午饭时间还在工作，你想要我证实一下吗?根据I guess not. He       on it at lunchtime可知他在午饭的时间正在做，故用过去进行时。故选B。
考点：考查动词时态。