单项选择题 Small talk with strangers (陌生人)is all interesting part (部分) of life in the United States. People often have short conversations (交谈) with people they don't know — for example. when sitting on the bus. waiting in line. or walking down the street. In fact. if you and the other person are the only people around. all talking Io someone can be impolite (无礼). Generally speaking. these conversations have three parts. greetings. small talk and leave-taking (告辞). In the first part. people say 'Hi' or 'Hello' and tell each other their names; in the second part people talk about everyday (日常的) topics such as the weather or sports; in tile last one. they say that they are happy to nicer each other and say goodbye.Talking with strangers is ______ in the United States.A．interestingB．impoliteC．important

多项选择题 赛前状态的生理变化主要包括（）。

多项选择题 “极点”出现后，采用哪些措施有利于消除“极点”？（）