英语语法：—Why do you look worried?
问题描述：
英语语法：—Why do you look worried?
—Fred left the company half an hour ago.His work ________ unfinished since.
A.left B.was left C.has left D.has been left
选哪个,为什么?
答
D.has been left
这是现在完成时的被动语态
unfinished是过去分词作主补 也就是原来的宾补
主动语态是 leave sth done句型
本句写成主动语态是 Fred has left his work unfinished since
注意 本题的关键是副词since ,该词作副词用时 只能与完成时 连用.
所以本题不选 B如果本题无sice 是否可以选B？可以 但最好写成并列句 。也就是一句话。—Fred left the company half an hour ago，and his work was left unfinished 。