Question

Our maths teacher set so difficult an examination problem ______ none of us worked out.

1. A.
   which
2. B.
   that
3. C.
   as
4. D.
   so that

Answer 1

C
試題分析：句意：我們的數(shù)學老師出了一個這么難的考試題，我們中沒人能做出這個題來。這里是定語從句，so……as，as引導的是定語從句，as在從句中賓語，故選C。
考點：考查定語從句的用法。
點評：本題難度適中。定語從句是高中階段必須掌握的語法項目，考生容易誤選AB，這里是特殊的固定搭配，不能用that或which，在結果狀語從句中that不作成分，故選C。
即學即練：I saw some trees，the leaves of  ______  were black with disease.
A. that        B. which        C. it         D. what
解析：B�？疾榉窍拗菩远ㄕZ從句的介詞+which結構。the leaves of which 相當于 whose leaves。