问题
选择题
—You seem tired, David.
—Yes. I _____ all day long and can’t wait to go to bed now.
A．am working
B．had been working
C．have been working
D．was working
答案
答案：C
考查时态。根据句意可知用现在完成进行时，句意:——戴维，你看起来很累。——是的，我工作了一整天，现在都迫不及待的的上床睡觉了。