Greetings
Americans are very friendly. They tend to greet each other with a smile, sometimes a handshake, and a friendly “Hello, how are you?” (which is not a question about your health) or “What's up?” Such a greeting is very common, and does not always require an answer. If an American friend greets you with “Hi, what's going on?” and walks away, do not feel offended1, it is a popular way of greeting. Also, the common phrase “See you later” is not an invitation for a visit, but a way to say “Good bye”. Americans are also very informal, and address each other by their first names from the time they meet, even with elders and people of authority2. Do not feel uncomfortable when someone asks you to use his/her first name, it is customary. If you are in doubt about how to address someone, you should first use the formal name and wait for them to suggest that you use the first name.
Gifts
As a rule, gifts are given to relatives3 and close friends. They are sometimes given to people with whom one has a casual but friendly relationship, such as a host or hostess, but it is not necessary or even common for gifts to be given to such people. Gifts are not usually given to teachers or others who hold official positions. The offering of gifts in these situations is sometimes interpreted4 as a possibly improper effort to gain favorable treatment5 from that person. Body Language
Keep in mind that unspoken signals by others may not mean what you think. Various gestures6 are automatic7 and vary from culture to culture. For example, burping8 after a meal in America is something that one needs to excuse himself/herself for doing. While in other countries, burping may be seen as a complement9 to the cook. If a person's words and gestures do not seem to match, it would be wise to ask the individual.
Dress
Casual dress is appropriate10 for the classroom. Students will, however, dress more formally for certain class presentations11. Casual dress is also appropriate for visits in people's homes, shopping or movie theatres. You might dress more formally for a special dinner or a special event at the University.
Personal Hygiene
To most Americans, personal hygiene12 is very important. They shower and wash their hair daily, and wear freshly cleaned clothes each day. Natural body odors13 are considered unpleasant and offensive, so deodorants14, colognes15 and other toiletries16 are used often.
Time
Americans are very time conscious and place high value on promptness17. Buses, trains, meetings and classes generally start on time.
问候
美国人待人非常友好，彼此往往以微笑互相问候，有时会握握手，并友好地问候一声：“嗨，你好！”（这可不是询问你的健康状况）或者说：“还好吧！”此类问候相当寻常，并不一定要求对方回答。如果你的美国朋友对你说一声“嗨，还好吗？”，说完就走开了，你可别感到不快，这种问候方式很普遍。此外，“稍后见”并非邀请你上门拜访，而是告别的另一种方式。美国人相当随意，见面就彼此直呼其名，哪怕对长者或有身份的人也不例外。若有人让你对其直呼其名，你大可不必感到难为情，习惯就是如此。如果你对如何称呼某人没有把握，应先用较为正式的姓氏称呼对方，然后等对方提示你直呼其名。
送礼
作为美国人的习俗：礼物只送给亲人或好友。有时，美国人也送礼给交往随意但关系友好的人士，诸如做东的男女主人。不过，此礼不是非送不可。通常也不给老师或其他官方人士送礼。这类情况下送礼，有时会让人理解为试图取悦他人以期从中受益，因而不合适。
体态语言
请牢记：他人的姿态语言所表达的不一定是你理解的意义。不同的体态语源自不同的习惯和文化。比如，在美国人看来，饭后打嗝是一种需要请求旁人原谅的不雅行为；但是在有些国家，打嗝却被视作餐后正常的现象。假如一个人的言语和姿势表现得不相衬， 聪明的做法是去问问此人。
着装
在教室里可以穿着随意一点。不过，在某些课堂展示中，学生们的穿着往往正式一些。前往别人家拜访，外出购物，或者上电影院，均可随意穿着。在大学里，若出席一个特别的宴会或者一项特殊的活动，还是穿着正式一点为好。
个人卫生
大多数美国人非常重视个人卫生。他们每天洗澡洗头，每天更换干净的衣服。散发出体味会令他人不快，让人讨厌，因此，美国人常常使用除臭剂、香水和其它卫生用品。
时间
美国人时间观念很强，重视守时。