开车从加返美：
Officer: passport please
I handed my passport and AP to him.
Officer: Why did you go to Canada?
I: Landing
Officer: Landing? hmm, you know you can only have one permanent residence
I: Yes I know. I will give up my Candian residence eventually.
Officer: then why did you land?
I: I spent time and money on it and just wanted to finish it. I also took this opportunity to visit some friends in Canada.
Officer: okay, you are all set now.
I: Thank you sir.