--- My dad bought me a new MP4 player, but I don’t know .
A. what to use
B. what to use it
C. how to use it
D. when to use it
网友回答
A. what to use
B. what to use it
(答案→)C. how to use it
D. when to use it
解析：A. 用什么 B. what to use it 说法有误 C. how to use it 如何使用它 D. 什么时候用它。句意：我爸爸给我买了一个新的mp4,但是我不知道如何用。故选C。