问题
选择题
--- Did you ask the guard _______ happened?
--- Yes, he told me all _______ he knew.
A．what; that
B．what; what
C．which; which
D．that; that
答案
答案：A
what happened是宾语从句. all 之后that he knew是定语从句.先行词是all,所以关系代词只能用that.