Don’t interrupt me. I letters all morning and have only finished five.
A. write
B. have written
C. have been writing
D. am writing
网友回答
A. write
B. have written
(答案→)C. have been writing
D. am writing
解析：考查时态。句意：别打扰我，我一上午都在写信，到现在才写好五封。现在完成时表示从过去某一时间开始的动作一直到现在还在继续。