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问题 选择题

一个物体沿着另一个物体表面滑动，其摩擦力的大小[ ]

A、只与物体表面受到的压力有关

B、只与物体受到的重力有关

C、与物体受到的重力和接触面的粗糙程度有关

D、与物体表面受到的压力和接触面的粗糙程度有关

答案

答案：D

选择题

Sometimes we fail and sometimes we succeed.It is how you react that makes a______ in life.

A．development

B．point

C．progress

D．difference
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单项选择题

There is virtually no limit to how one can serve community interests, from spending a few hours a week with some charitable organization to practically full-time work for a social agency. Just as there are opportunities for voluntary service (1) (VSO) for young people before they take up full-time employment, (2) there are opportunities for overseas service for (3) technicians in developing countries. Some people, (4) those who retire early, (5) their technical and business skills in countries (6) there is a special need.

So in considering voluntary or (7) community service, there are more opportunities than there (8) were when one first began work. Most voluntary organizations have only a small full-time

(9) and depend very much on volunteers and part-timers. This means that working relationships are different from those in commercial organizations, and values may be different. (10) some ways they may seem more casual and less efficient, but one should not (11) them by commercial criteria. The people who work with them do so for different reasons and with different (12) , both personal and (13) . One should not join them (14) to arm them with professional experience; they must be joined with commitment to the (15) , not business efficiency. Because salaries are (16) or non-existent many voluntary bodies offer modest expense. But many retired people take part in community service for (17) , simply because they enjoy the work.

Many community activities possible (18) retirement were also possible during one’s working life but they are to be undertaken (19) seriously for that. Retired people who are just looking for something different or unusual to do should not consider (20) community service.

16（）

A.lime

B.small

C.large

D.big
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