Frank:Are you doing anything on Saturday evening?
Bob: Nothing special, ________ ?
Frank: We′d like to have you and your wife" over for dinner this Saturday evening.
Would you be able to come?
本题考查有关邀请的对话。Frank问Bob周六晚上是否有空，Bob说有，接下来就应该问有什么事。B选项的why(为什么问我有没有空呢，有事吗?)符合题意。what单独使用时表示惊讶，what’s the matter(出了什么事?)和what do you mean(什么意思?)都不合适。