问题
选择题
______ him well, I would have invited him to my birthday party.
A．Had I known
B．Should I know
C．If I know
D．If I knew
答案
答案：A
考查虚拟语气。根据句意考查与过去事实相反的虚拟语气，故从句用had + v-ed。Had I known =" If" I had known。句意：如果我很了解他的话，我将邀请他参加我的生日晚会。