Which period of history would you most like to have lived in?
你最喜欢生活在哪一个历史时期？
You must signal which way you are going to turn.
你要朝哪个方向转，必须发出信号。
There are two points which I wanted to make.
我想要指出的`有两点。
We are still friends, though, which is good.
不过我们仍然是朋友，这令人感到欣慰。
Which part of Japan do you come from?
你是日本哪个地区的人？
There is some noise in the data which needs to be reduced.
资料里有一些需要删除的不适用信息。
