7[.单选题]It was clever __ at the answer in two minutes.
A.of him to arrive
B.for him to arrive
C.for his arriving
D.of his arriving
[解析]比is 形容词 of 名词/代词 不定式，of后的名词/代词为不定式的动作发出者。
8[.单选题]It is difficult to distinguish one twin __ the other.
9[.单选题]My parents always buy __ my birthday.
A.anything nice to
B.anything nice for
C.something nice to
D.something nice for
10[.单选题]To travel from England to Scotland you __ a passport.