题干

下列关于材料的说法中,正确的是(  )

A:三大合成材料是指塑料、合成纤维和复合材料

B:热塑性塑料与热固性塑料均具有线型结构,加热到一定温度都能软化、熔化

C:复合材料一般是以一种材料作为基体,另一种材料作为增强剂

D:钢化玻璃与普通玻璃的主要成分不同

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答案(点此获取答案解析)

C

同类题1

阅读理解

    What are American high schools like? Well, I'm happy to tell you what I know.

    When I started school here, it had already been a week since the school opened. At this school, freshmen usually go on a trip for about three days at the beginning of school. Unfortunately I missed that wonderful trip, which would have been the best time to get to know my classmates. I was really sad. I wished I'd known about it earlier.

    Despite the disappointment, however, I gradually adapted to my new life and school.

    There is a space in the basement of the teaching building where students chat and meet each other. As we do not always have the same classrooms and classmates, the school wants us to get to know each other there. Students usually come to school early, sit in that space and have fun. Around the space, there are many lockers for students to leave their books in, so that students do not have to carry a heavy schoolbag everywhere.

    It really surprises me that we have almost no textbooks. We only have textbooks for World History and Algebra 2 and they are big and heavy, like bricks. For other classes, we only need binders (活页夹) with paper in them. Without textbooks, students learn things freely and actively. For example, my humanities teacher just teaches us what is in her mind at the time. We never know what we will learn.

    Another difference between American schools and Chinese schools is that American schools care about students' morality more than their academic studies. For example, if you do not finish your homework, you will just be asked to do it later, but if you cheat or lie, you will get a warning or even be kicked out.

    I think that most students here are good at schoolwork as well, but compared to Chinese students, they can make learning a more joyful experience. I think we should take the good points from our two different kinds of education to perfect our approach to studying.

同类题3

阅读短文《拒绝句号》,完成题目。
                                                                                                  拒绝句号
       一定会有一些朋友反对我这个标题。他们会说多好的句号啊!句号表示一种完成,一种圆满,一种有志者事竟成,一种成果与收获,或者干脆把这溜圆的句号看成一个个饱满的果实。它们还会问我,当你完成一部几十万字的长篇小说,在那最末一行画上一个句号时,难道你没有如释重负、飘飘欲仙般的感受?没有那种大功告成后该痛快干杯的喜悦吗?
         当然,这样的句号我也喜欢。但人生还有另一种句号。
         打个比方,你在一条路上走,走着走着,忽然有一种“尽头感”时,这句号就隐隐出现,如果你停下来,你足下就清晰地现出一个句号。这条路可不是做一件事时那短短的距离,它是人生追求的路、艺术探索的路和事业奋斗的路。这路原本无止无休,你在任何一处都可以起步,踏上征程;你也可以在任何一处画个句号,退了出来。无论什么都可以成为句号的缘故:那精疲力竭的放弃、自寻清闲的逃逸、江郎才尽的低头认输,乃至收获后的自满自足,甚至在目标达到之后,辉煌的目标也会划为一个句号,尽管这句号闪闪发光。句号,就是停止,就是终结,就是事物最终变为有限的、死去的符号。
         我说的是这种句号。可怕的是,这些句号总是不知不觉地出来。你呢,不知不觉地完结。想想看,你曾经做过了哪些有益的事?究竟是什么时候并怎样弃你而去的?句号往往又是和人的自足、人的彻悟、人的惰性连在一起的。所以句号大多是人心甘情愿给自己画上的。人随时可能舒舒服服给自己画个句号,休止了自己。
         因而,我害怕句号。我对句号保持着近乎神经质的警惕。在与句号的斗争中,我一边感到生命的活力,常常闻到自身肌肉搏斗后散发出热烘烘的清香;一边认识到这原是生命存在所必须进行的奋争,也是与自身惰性与保守的对抗。当然,它何其艰难!跨过每一个句号,都需要付出双倍的力量,其中一半是创造力。然而,只要在人生或艺术的道路上,消灭一个句号,便开始一段崭新的充满诱惑的路。我们还会发现,被我们拒绝和消灭的句号,最终竟然会变成逗号。你是不是也会从中得到启示:
        最积极和充实的人生,是不断努力地把句号变为逗号。