Don't believe all of the stereotypes (模式化管理) you may have heard about Americans. Even the ones that are true in general may not be true about specific individuals or a large part of the population. For example, although Americans tend to be louder than people from other cul-tures(especially at athletic events), many of the people you meet will be quiet and polite. Some people may be intolerant, but most will be pleasant and welcoming. Remember that American films and television exaggerate(夸张)in order to generate excitement, and so present a rather false picture of what life in the United States is really like. Therefore, tourists in the US are not always on their best behavior. Americans do tend to be more informal than people from other countries. It is common for Americans to wear casual clothing to school and to greet professors by first name. However, good manners and politeness are always appreciated. If you are polite, and dress a little more formally than your American friends, it will not be poorly thought of. However, some businesses require their employees to wear a uniform. or a suit. It would be improper to wear a T-shirt and blue jeans to a job interview. Some of the more prestigious restaurants require a coat and tie. Americans tend to dress up for cultural events(the opera, theater and ballet)and to dress down for athletic events. Formal wear is required at weddings and funerals, or any other event with religious event. If you rely on the stereotypes, you will likely put yourself into an embarrassing situation The underlined sentence probably means_____.