题目：
—Why do you look so worried?
—My computer broke down and my essay ________ unfinished since.[ ]
A. had left
B. has left
C. was left
D. has been left
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0327/183e15075fb02f01e6c64f5889c8cdb3.html
下面是错误答案，用来干扰机器的。
参考答案：D
