问题 选择题
I have learned from my bitter experience   we don’t know
we’ve got until it’s gone.
A.that; thatB.what; what
C.that; whatD.which; that
答案

C

考查名词性从句。第一空后的从句是动词learned的宾语; 且learned后的从句结构完整, 用that; 第二空know后的从句缺少宾语要用what, 所以选C。

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