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问题 选择题

古诗词是古人留给我们的宝贵精神财富．下列诗词中不涉及化学变化的是（　　）

A．好雨知时节，当春乃发生

B．爆竹声中一岁除，春风送暖入屠苏

C．千锤万凿出深山，烈火焚烧若等闲

D．春蚕到死丝方尽，蜡炬成灰泪始干

答案

A、下雨的过程中没有新物质生成，属于物理变化．故选项正确；

B、燃放烟花爆竹能生成二氧化碳等新物质，属于化学变化．故选项错误；

C、石灰石高温煅烧时能生成氧化钙和二氧化碳等新物质，属于化学变化．故选项错误；

D、蜡烛燃烧能生成水和二氧化碳等新物质，属于化学变化．故选项错误．

故选A．

单项选择题

Teachers need to be aware of the emotional, intellectual, and physical changes that young adults experience. And they also need to give serious (51) to how they can be best accommodate such changes. Growing bodies need movement and (52) , but not just in ways that emphasize competition. Because they are adjusting to their new bodies and a whole host of new intellectual and emotional challenges, teenagers are especially self-conscious and need the (53) that comes from achieving success and knowing that their accomplishments are admired by others. However, the typical teenage lifestyle is already filled with so much competition that it would be (54) to plan activities in which there are more winners than losers, for example, publishing newsletters with many student-written book reviews, (55) student artwork, and sponsoring book discussion clubs. A variety of small clubs can provide multiple opportunities for leadership, as well as for practice in successful (56) dynamics. Making friends is extremely important to teenagers, and many shy students need the (57) of some kind of organization with a supportive adult (58) visible in the background.

In these activities, it is important to remember that the young teens have (59) attention spans. A variety of activities should be organized (60) participants can remain active as long as they want and then go on to something else without feeling guilty and without letting the other participants down.

60().

A. if only

B. now that

C. so that

D. even if
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单项选择题

机体处于应激如创伤、手术、感染等情况下，能量代谢的变化中，错误的是（）。

A.机体出现高代谢和分解代谢

B.脂肪动员加速

C.蛋白质分解加速

D.处理葡萄糖能力增强

E.机体处于负氮平衡
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