I would like to send this by registered mail, please.
我想把这封信挂号寄出。
What would you say if I told you I couldn't go with you?
如果我告诉了你我不能和你一起去你将说什么?
In their efforts to persuade us to buy this or that product, advertisers have made a close study of human nature and have classified all our little weaknesses.