“为师夷长技以制夷”而编写的书是（ ）
鱼必须生活在水里，离开水一段时间就会死亡．对此最恰当的解释是（ ）
Clerk: ____ I help you?
Mary: Yes, please. I want a sweater.
Clerk: What ____ do you want?
Mary: Blue.
Clerk: Here you are.
Mary: How ____ is it?
Clerk: Nine dollars.
Mary: I'll ____ it. Thanks.
Clerk: You're ____.
