If you go abroad, first you are expected to bring your passports. (two), you should make an effort to know some customs. For example, when you greet people in Korea, you should bow. You'd better take off your shoes you drop by someone's home in Japan. You can't knock your empty bowl at dinner in China. In France, you can greet people by kissing. In Washington D. C., the capital of the USA, you (suppose) to value time, especially in their busy season, or your friends may get mad.
The table (manner) are different in different countries, too. Once I visited the eastern coast of the USA as exchange student. Though the host family went out of their way (make) me feel at home and the granddaughter tried her best to make me (relax), I didn't get used to the basic manners there. I was born in a northern city all. I think everyone behaved well except me. I ate lunch with my two elbows on the table. I didn't clean off the chalk on the blackboard at noon. I still feel nervous these days.
So I think a teenage student should get some (suggest) before going abroad. The good manners are worth (remember) gradually.
