Question

In ______ preparation for the launching of Shenzhou Ⅶ, scientists need ______ knowledge of weather changes.

1. A.
   the; the
2. B.
   a; ∕
3. C.
   ∕; a
4. D.
   the; a

Answer 1

C
in preparation for 固定搭配；a knowledge of 某一门知识，这个时候可数。