胃肠超声检查前准备下列哪项是错误的（）。

[单选题]Informal conversation is an important part of any business relationship. Before you start a discussion, however, make sure you understand which topics are suitable and which are considered taboos (禁忌) in a particular culture. Latin Americans enjoy sharing information about their local history, art, and customs. They expect questions about their family and are sure to show pictures of their children. Yon may feel flee to ask similar questions of your Latin American friends. The French think of conversation as an art form, and they enjoy the value of lively discussions as well as disagreements. For them, arguments can be interesting-and they can cover pretty much or any topic-as long as they occur in a respectful and intelligent (智慧的) manner. In the United States, business people like to discuss a wide range of topics, including opinions about work, family, hobbies, and politics. In Japan, China, and Korea, however, people are much more private. They do not share much about their thoughts, feelings, or emotions because they feel that doing so might take away from the harmonious (和谐的) business relationship they’re trying to build. Middle Easterners are also private about their personal lives and family matters. It is considered rude, for example, to ask a businessman from Saudi Arabia about his wife or children. As general rule, it’s best not to talk about politics or religion (宗教) with your business friends. This can get you into trouble, even in the United States, where people hold different views. In addition, discussing one’s salary is usually considered unsuitable. Sports is typically a friendly subject in most parts of the world, although be careful not to criticize a national sport. Instead, be friendly and praise your host’s team.Which is typically a friendly topic in most places according to the author

[判断题]在移频自动闭塞区段，移频信息的传输是按照运行列车占用闭塞分区的状态，迎着列车运行方向，自动地向前方闭塞分区传递信息的。

[判断题]电气设备的金属外壳必须接地（接零），接地线要符合标准，有电设备不准断开外壳接地线。

[多选题]中世纪高等教育的特点包括（）

[多选题]以下有关计算机说法正确的是（）。

[问答题]简述国际私法中对结婚形式要件的法律适用的几种不同实践。

[单选题]自动化检票的层次有（）.

[单选题]（）是一种选频电路。它能选出有用的信号，而抑制无用的信号，使一定频率范围内的信号顺利通过。

[问答题]空分装置在临时停车时的冷损失有哪些？

[多选题]调度集中系统的主要功能是，对列车运行进行直接（）