材料一：一位妈妈的苦恼：“我的女儿一直都挺懂事的，可是自从上初中后就变了。我让她往东她偏往西，越来越不听话，而且还学会了顶嘴，真是气死我了。”其实很多家长都有这样的苦恼。

材料二：关于“顶嘴”的调查。

——上个星期，和爸爸约定好如果我作业完成了就带我去迪斯尼玩。可等我完成了他却改口说，等你考上班级前十名，考不上就别想了。我真的特别生气，为什么你们大人这么言而无信……

——有次我只是想帮她分担一点家务，不让她很辛苦，不小心摔坏了碗。妈妈就过来向我大吼：“谁让你洗碗了!有这个闲工夫还不去看书!”我感到很委屈，就向她顶嘴了。

——我已经长大了，有了自己的观点，和父母看法不一致的时候，如果不大声“顶嘴”，根本没有威力，我们就应该勇敢地说出自己的想法。

……

结合所学知识回答：

    With air pollution making much difference to many of Chinese cities, parents are calling for the installation(安装) of air cleaners in classrooms. There has been much debate over whether air cleaners should be used in China's schools. Some parents have donated cleaners to their children's classrooms, while others raise money together to make the purchase(购买). “Our school bought air cleaners last year. We did a little fund raising, with each parent throwing in several hundred for that,” said one parent.

    However, the idea of installing air cleaners for all the classes has been refused by some schools. Liu Liangcheng, vice-principal of Beijing's Taipinglu Primary School, says installing air cleaners bought by parents may lead to problems. “We have refused air cleaners bought by parents before, as there are clear and strict rules against educational fees. We can't just break the rules here. And without standard guidance (指示) from local authorities(权威部门), it is hard to decide on the brand of the cleaner, installation and even safety of the device(设备).”

    Moreover, experts say air cleaners can cause other health problems. Deng Gaofeng who works for the China Academy of Building Research says. “ In the classroom, if we keep windows and doors closed, the concentrations (浓度) of CO₂ will double from 1,000 PPM to some 2,000 PPM. According to national safety standards, the highest level should not be more than 1,500.” In addition, experts say air cleaners on the market are mostly designed for homes or offices. Evaluation(评估) is needed to know whether they are suitable in classrooms.

    It seems whether air cleaners should enter China's schools is an ongoing question. It still requires a more detailed plan.

阅读以上信息，用恰当的单词完成下面的表格，每空一词。

Topic : Should air cleaners be installed for students in school?

回答下列问题：

①氨基酸                   ②C,H,O,N等元素        ③氨基酸脱水缩合 

④一条或几条肽链接在一起     ⑤多肽                   ⑥蛋白质．