Who is the man---was standing at the door?A.who B.which C.that D.as
问题描述：
Who is the man---was standing at the door?A.who B.which C.that D.as
答
选C 这个句子是定语从句,先行词是人,所以用who或者that,但是主句用who提问了,这里只能选that