问题补充：
-- Hi, Rob! ?
---I’m fine. I’ve just been to my first language class.
A. What’s wrong with you
B. What did you do
C. How are you doing
D. How do you do
答案：
A. What’s wrong with you
B. What did you do
(答案→)C. How are you doing
D. How do you do
解析：--句意：喂，Rob，你好吗？--我很好，我刚去上语言课了。What’s wrong with you你怎么了；What did you do你做了什么事；How are you doing？你好吗？How do you do你好，用于初次见面时的用语，答语仍用它。故选C。
