问题
选择题
– Why does she look so tired?
-- She ________ all the morning and she still hasn’t finished it.
A．cleaned
B．was cleaning
C．has been cleaning
D．has cleaned
答案
答案：C
clean这个动作，之前就发生了，一直到现在还没完成，还在继续，因此用现在完成进行时态。