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问题 选择题

列车在轨道上作匀速直线运动，一名乘客在车厢里竖直向上跳起，那么，这位乘客的落地点（　　）

A．在起跳点位置

B．在起跳点的前方

C．在起跳点的后方

D．以上情况都有可能

答案

因为乘客随匀速行驶的列车一起做匀速直线运动，当乘客竖直向上跳起后，乘客由于惯性，在水平方向上仍保持原来的速度和方向做匀速直线运动，所以等他落下时，仍落在起跳点位置．

故选A．

填空题

语法填空。

     Not all cultures greet each other the same way. Each may have its own way 1______ (express) feelings.

In Britain, people may keep 2______ certain distance and they usually do not touch 3______ (strange) as soon

as they meet. In Japan, they may bow 4______ each other when they meet. In France, people shake hands and

kiss each other twice 5______ each cheek when they meet people they know. And in South American countries,

Spain or Italy, people get close to others and are 6______ (like) to touch them. 7______ in Middle East or some

Muslim countries, men stand quite close to other men to talk; they just nod at women and seldom shake hands

with them. None of these actions is 8______ good or bad, they are simply the ways 9______ cultures have

developed. Knowing some of them can help you avoid 10______ (difficult) in communication.

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单项选择题

单车试验器的压力表应每（）校对一次。

A.6个月

B.3个月

C.1个月

D.1年
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