1. You will want two trees about ten feet apart, from ________to suspend your tent.
   A there         B then            C which             D where

    2. That was so serious a matter that I had no choice but ______the police.
   A called in      B calling in         C call in            D to call in

    3. Americans eat ________as they actually need every day.
   A twice as much protein             B protein twice as much
   C twice protein as much             D protein as twice much

    4.The more we looked at the picture, ____________.
    A the better we like it          B we liked it less
    C it looked better             D the more we liked it

    5. His method of doing research work is hardly appreciated; he feels inferior________ others.
    A than        B as         C with           D to 
 
    1. 正确答案：C
    例题解析：    介词+关系代词+不定式作定语，只有which 是关系代词。

    2. 正确答案：D
    例题解析：Have no choice but 后要带接to 的不定式，意思是 只能……别无选择。

    3. 正确答案：A       
    例题解析：译文：美洲人每天所食用的蛋白质是他们实际需要的两倍。倍数+as+形容词+as，表示倍数

    4. 正确答案：D
    例题解析：The +比较级，the+比较级，表示越……，越……。

    5. 正确答案：D  
    例题解析：译文：他的科研方法未得到赏识，他感到低人一等。
 Inferior，superior，perfect本身含有比较意义，故表示比较时，其后不用连词that，而用介词to 指出比较对象。