Question

--- Tom, have you seen your brother?

--- Oh, I saw him ________ basketball on the playground on my way home.

1. A.
   to play
2. B.
   plays
3. C.
   playing
4. D.
   played

Answer 1

C
动词see后面常跟复合宾语，构成see sb. do sth.或see sb. doing sth. 结构。前者侧重“看见动作的完成或动作的全过程”，后者侧重“看见动作的进行或动作过程的一部分”。句意：在我回家的路上，我看到他正在操场上打篮球。故用see sb. doing sth.。故选C。