Question

Having failed my English exams, I decided ________ science subjects.

1. A.
   to concentrate
2. B.
   to concentrate with
3. C.
   to concentrate on
4. D.
   to concentrate to

Answer 1

C
本题主要考查concentrate一词的搭配用法，从左栏的归纳讲析中可以看到，与之连用的介词on，因此就不难排除A、B、D三项。全句意为“我因英语考试不及格而决心专攻理科”。