问题
选择题
—What time will Mr. Brown be back to China?
—Sorry. I don’t know______.
A．when did he go abroad
B．why he is going abroad
C．how soon will he be back
D．how long he will stay abroad
答案
答案：D
本题回答语know后跟的是一个宾语从句，应该用正常的陈述句顺序，故不选AC，本题上句问的是时间，回答语和时间有关的只有D项，故本题选D。