【题目】Sorry. I know you here, otherwise I would have greeted you.
A. don't ... are B. don't ... were
C. didn't ... are D. didn't ... were
在线课程【答案】D
【解析】
考查时态。句意：对不起。我不知道你在这里，否则我就会跟你打招呼。根据otherwise I would have greeted you.可知此处是虚拟语气，与过去的事实相反，所以句子用一般过去时态，故答案为D。