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问题 单项选择题

弹簧式安全阀的阀瓣被弹簧压紧在阀座上，平时阀瓣处于关闭状态，它是利用( )来平衡介质的压力。

A．弹簧

B．弹簧的压力

C．阀办

D．介质

答案

参考答案：B

解析： 弹簧式安全阀是利用弹簧的压力来平衡介质的压力，阀办被弹簧紧压在阀座上，平时阀办处于关闭状态。

单项选择题

确认和追究个人在集体行为中的责任，最好的方法就是（）。

A．根据制度赋予他们的特定身份

B．根据制度赋予他们的特定义务

C．根据制度赋予他们的特定权力

D．根据制度赋予他们的特定职责
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填空题

Many animals engage in play，but homo sapiens is the only animal (1) have invented sports.Since sports are an invention，a part of culture (2) than an aspect of nature，all definitions of sports are somewhat arbitrary. (3) sports are a human universal found in every known culture or a (4) unique to modern society depends upon one’s definition of sports.Men and (5) have always run，jumped，climbed，lifted，thrown， and wrestled，but they have (6) always performed these physical activities competitively. Although all literate societies seem to (7) contests of one sort or another in which men， and sometimes women， (8) in displays and tests of physical skill and prowess，sports may be (9) defined as physical contests performed for their own sake and not for (10) ulterior end.According to this strict definition，neither Neolithic hunters nor contestants (11) religious ceremonies such as the ancient Olympic Games were engaged in sports. (12) on the stipulation that sports must be performed for their own sake (13) the paradoxical elimination of many activities which are usually thought of as (14) ，such as exercises done for the sake of cardiovascular fitness，races run (15) satisfy a physical education requirement，ball games played to earn a paycheck. (16) definition also means abandonment of the traditional usage in which"sport，"derived (17) Middle English disporter，refers to any light hearted recreational activity.In the. (18) of some 18th- century aristocrats，a game of backgammon and the seduction of (19) milkmaid were both considered good sport，but this usage of the term (20) become archaic.
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