净化空气，需要你我
尊敬的领导，评委老师，亲爱的同学们：
大家好！
我是 号选手，今天，我演讲的题目是《净化空气，需要你我》。
历史是一面镜子，它呼唤着我们的理性和良知。曾几何时，我们追忆着“蓝蓝的天上白云飘”的美丽天空；曾几何时，我们畅想着“清晨第一缕阳光，映射出纤细身影”的柔润空气，而这些——已成为了我们美好的回忆。现在，终日的乌烟瘴气，阴霾笼罩，实在令人不快。怎样才能净化空气，还我美丽晴空？这，需要你，需要我共同的努力！
想要净化空气，我们首先要知道空气污染的原因，有人认为污染的最主要原因是工业排放，每年由于工业排放造成的的污染都十分严重。其次，便是尾气排放，它在空气污染中占据的比例也很大，而且这些空气中的颗粒物会被吸入肺里，当肺部堆积过多的颗粒物时，就会给我们的健康带来影响。
那么，我们是不是就没有办法来净化空气了呢？回答当然是否定的。防止空气污染恶化下去的办法有很多：增加绿地覆盖率就是一个不错的办法，我们在生活中可以多种草植树，利用课余时间在空地中多种几棵树，植上一片草，这一片片绿茵茵的草地，一棵棵郁郁葱葱的树苗，不仅可以吸收二氧化碳，还能为我们的家园添上了生机。
想要有效的净化空气，也要从我们自身的小事做起。作为初中学生，我们每天上学的时候，尽量不要乘坐私家车，可以选择步行或骑自行车，这样，既减少了汽车尾气的排放，还锻炼了我们的身体。
想要有效的净化空气，还要从节能减排做起。空调——是我们在夏天必不可少的解暑工具，但它却有着不为人知的“故事。”如果空调每天开启八小时，使用90天，那一天的耗电就是720度，向大气中排放的二氧化碳为565.2千克，这些就需要6棵树来“还债”！
自然是人类的摇篮，绿意是自然地颜色，新鲜的空气则是自然的生命，我们需要一方净土，需要一片蓝天，净化空气，需要你，需要我，一起营造湛蓝的天空，净化清新的空气！
Good afternoon everyone I\'m contestant of number 15, I’M Ma Dongxue.I’m from Cla 2 Grade 2of Zhang Gezhang Middle School.My speech title is
It’s time to purify the air.
Blue sky and white clouds，which was common in the past, but now we can rarely see them, especially in cities and industrial districts.The hazy weather becomes more frequently, which makes us unhappy and unhealthy.So it is high time to take actions to purify the air.To purify the air, first we should find the causes of air pollution.As we all know industrial emiions are the major cause of air pollution.And the off-gas produced by vehicles is another cause.The polluted air contains many tiny particles and it can be inhaled into human’s lung, which is harmful for people.
Are there any ways to purify the air? Of course, there are.We have so many ways to prevent the air pollution getting worse.Everyone can help cut down on air pollution by making simple changes in our daily life.As a student, we can plant more trees using our free time to increase Greenland coverage rate.On the other hand, we can go to school by bike or by public transportation, and so on.It can not only reduce emiion but also exercise.Changing small habits can make a big difference.Summer is coming and the air conditioner is important for us in hot summer, but there is something we do not know.If an air conditioner works eight hours per day, total 720 degrees of electricity will be used up and 565.2 kg carbon dioxide will be released into the air.So we could start using the air conditioners as le as poible.
We cannot live without fresh air and it is time to take actions to purify the air.Small actions can make a big difference.Let’s work together.
