电火花线切割采用负极性加工，工件接脉冲电源的负极。 - 查题网

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国家开放大学 / 模具制造工艺

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电火花线切割采用负极性加工，工件接脉冲电源的负极。
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高等数学2

题型描述: 阅读理解In the United States, it is not customary to telephone someone very early in the morning． If you telephone him early in the day, while he is shaving or having breakfast, the time of the call shows that the matter is very important and requires immediate attention． The same meaning is attached to telephone calls made after 11:00pm． If someone reeives a call during sleeping hours, he assumes itˊs a matter of life or death． The time chosen for the call communicates its importance． In social life, time plays a very important part． In the U. S. A． guests tend to feel they are not highly regarded if the invitation to a dinner party is extended only three or four days before the party date． But it is not true in all countries． In other areas of the world, it may be considered foolish to make an appointment too far in ad-vance because plans which are made for a date more than a week away tend to be forgotten． The meaning of time differs in different parts of the world． Thus, misunderstandings arise between people from different cultures that treat time differently． Promptness is valued high-ly in American life, for example． If people are not prompt, they may be regarded as impolite or not fully responsible． In the U. S. no one would think of keeping a business associate waiting for an hour, it would be too impolite． A person who is 5 minutes late, will say a few words of explanation, though perhaps he will not complete the sentence．1、 What is the main idea of this passage? A. It is not customary to telephone someone in the morning and in sleeping hours in the U．S． B. The role of time in social life over the world． C. Not every country treats the concept of time as the same． D. If people are not prompt, they may be regarded as impolite or not fully responsible in the U．S． 2、 What does it mean in the passage if you call someone during his or her sleeping hours? A. A matter of life or death． B. A matter of work． C. You want to make an appointment with him or her． D. You want to see him or her． 3、 Which of the following time is proper if you want to make an appointment with your friend? A. at 4:00 am． B. at 4:00 pm． C. at the midnight． D. at 7:00 am． 4、 Which of the following statements is true according to the passage? A. Promptness is valued highly in American life． B. There is no misunderstanding arising between people from different cultures about the concept of time． C. It may be considered foolish to make an appointment well in advance in the U.S.A．． D. In the U．S．A． guests tend to feel they are highly regarded if the invitation to a dinner party is extended only three or four days before the party date． 5、 From the passage we can safely infer that ． A. if a person is late for a date, he neednˊt make some explanation B. itˊs a matter of life or death if you call someone in day time C. it makes no difference in the U.S. whether you are early or late for a business party D. the meaning of time differs in different parts of the world统考英语A

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?（）是为基本生产单位提供辅助产品或劳务的生产单位。 A.生产服务部门 B.辅助生产单位 C.基本生产单位 D.?行政部门 E.生产运营管理