问题
选择题
If you had joined the chat room ten minutes ago, you _____ what we were talking about.
A．will know
B．are knowing
C．can know
D．would have known
答案
答案：D
考查虚拟语气。根据语境考查与过去事实相反的虚拟语气，故主句用would have done。句意：如果你一分钟之前加入聊天室的话，你就会知道我们在谈论什么的。