问题补充：
- You can use MSN to talk with your friend on the Internet.
-I know. But can you tell me?
A. what I can use it
B. how can I use it
C. why can I use it
D. when I can use it
答案：
A. what I can use it
B. how can I use it
C. why can I use it
(答案→)D. when I can use it
解析：句意：--你能用MSN与你的朋友在互联网进行谈话。--我知道。但是你能告诉我我什么时候能用它。分析考查宾语从句，宾语从句要用陈述语顺，而第一项用引导词为what后面就不用it,因此不正确。选项中只有第四项符合。故选 D
