这时候,博学多才妈妈回来了,见我们这副垂头丧气的模样,不禁哈哈大笑起来,我和表哥异口同声地问:“难道你有什么好办法吗?”“当然喽!”妈妈自信地说。只见妈妈拿来了一把螺丝刀,一只手拿住瓶身,另一只手拿着螺丝刀在瓶盖边缘轻轻一撬,只听见“啪”得一声响。紧接着妈妈把水果罐头给我,说:“现在,你再试试看。”果然奇迹出现了,我居然轻而易举的打开了瓶盖,我们惊讶得瞪大了双眼。“这究竟是怎么回事呢?”我充满好奇地去问妈妈为什么,妈妈让我自己找答案。
我顾不得吃水果罐头,就一头扑进了书房里,拿起《十万个为什么》翻起来。原来,这是因为生产商为了延长保质期,罐头中的空气被抽空了,形成了真空状态。因为大气压力所至,所以要在开瓶盖时,先把放进空气,使内外气压平衡,就很容易把盖子打开了!
真的是这样的吗?我决定做个实验来证明。说干就干,我拿来已被表哥吃完的水果罐头,用钉子凿了一个小洞,然后用针筒把里面的空气吸光,成真空状态,塞上棉花。我企图用力把盖子打开,可结果可想而知,跟刚才一样,怎么打也打不开。接着,我把棉花拿掉,空气迫不及待地从小孔拥进瓶中,这时,我很轻松地打开了盖子。结果证明,《十万个为什么》中的解释是正确的。
我明白了这个道理,也明白了科学的重要性,否则,又要闹出像今天这样的笑话了!所以我以后一定会认认真真地学好科学,将来为中国人民造福,祖国的建设作出贡献!
as we know , water is very important to man, we can’t live without water. the amount of water which is suitable to drink is less and less. but some people don’t care about it .they waste a lot of water in their daily life. even worse, they pour dirty water in to rivers. they throw rubbish into rivers , too. many rivers and lakes are seriously polluted.something must be done to stop the pollution. only in this way can we live happily. if we don’t save water, the last drop of water will be a tear-drop of us.
we know that despite the fact that seventy percent of the earth's surface is covered with water, only a little part of it is fresh water. yet the demand for fresh water in our daily life and in industry seems great. moreover, with the expansion of the population and development of industry, the amount of the fresh water needed will increase even rapidly. it is estimated that if such a trend continues, the fresh water on earth will be exhausted very soon. what is worse, more and more water resources are being polluted, making the water unfit to use.
in addition,we must warn the people of the importance of water and the danger we are facing.for example, in most asian societies where rice is the staple food, the water used after cleaning rice contains various nutrients for plant growth and is an excellent detergent to flush the toilet. furthermore, the intriguing idea of converting the inexhaustible sea water to fresh water supplies will be the ultimate solution.
水——我们的朋友 平达曾说过:“自然界的一切事物中,唯有水最珍贵。”是啊,水是我们的朋友,没有了水,就没有了我们。让我们一起与水做个好朋友吧! 水看见人们不节约用水,伤心地说:我对人类的所作所为感到不满,我为人类做了那么多的贡献,可人类总是滥用我。这样既会导致水源的\'流失,又会严重影响生态环境。 在生活中,处处都要用到水。洗菜要用水,洗车要用水,洗澡要用水??,这往往会浪费很多水。其实,请把水龙头开小一点,把废水再次利用,这样我们就能与水做好朋友了。比如:洗菜水可以浇花;洗澡水可以冲马桶??这样,不仅能节约用水,还对别的事物有好处呢! 如果水能这
样一滴一滴的节约起来,虽然不是太多,但是全世界人民都这样做,怎么会没有水呢? 人们可知道,世界上有许多地方水都很少,有些人,因为喝不上水,而死去,他们说:“请他们喝酒,不如请他们喝水。”下雨天,曾是他们最快乐的日子,他们可以用雨水洗澡,还能接水,以后用。他们把水当做奇珍异宝, 每次喝水都要去很远的井里去挑,那井里的水比黄河水还浑浊,比海水还难喝。由此可见,他们是多么爱水啊!如果我们能节约用水,他们的生
活难道会这样吗? 不节约用水,不但会导致水源的流失,还会影响生态环境。 有些工厂既不节约用水,还排放污水放到河流中,这样,水不仅流失了,还会影响生态环境。
我怀着十二份的好奇心来到作文餐馆。透过明亮的玻璃,看见里面座无虚席,有的`认真地吃,有的专心地写,一个个旁若无人的样子。这可奇怪了,我走进去问正专心在写作的老爷爷:“老人家,您这是在干什么?”老爷爷抬起头来,摸摸胡子:“对呀!我在写作文。”“您老——怎么也写作文?”老爷爷笑呵呵地说:“对呀!一走进这个餐馆,每个人都会有写作的***。你瞧,那边才上幼儿园的小朋友都写起了作文。”
正在这时,一名热情的服务员阿姨走上前来,笑眯眯的对我说:“小同学,请到里边雅座去坐吧!”我刚坐下,另一位服务员叔叔就为我递上菜单,只见菜单上写着:作文巧克力,能活跃写作思维;作文可比克,能激发写作***;作文奇多,能提高观察能力;作文薯条,能丰富写作素材;作文鸡翅,能补充好词佳句;作文汉堡,能产生写作灵感;作文热狗,能……看着这些菜肴,我高兴地手舞足蹈。赶紧点菜,每一样各点一份。然后狼吞虎咽地吃了起来,差点吃的撑破了肚皮。吃饱喝足了,我就拿出钱买单,没想到服务员阿姨摆摆手:“小朋友不用付钱,只要你留下一篇让我们满意的作文就行了!”
这难不倒我,吃了刚才那么多神奇的点心,我的写作思维像打开的闸门,一下子喷涌而出。不到三分钟,一篇文字优美的作文就在我的笔下诞生了。
作文餐馆,真让我感到其乐无穷啊!
Some people think studengts need not do any housework。They think the only thing students need do is to study well。 I don’t think so。 It is good for students to do some housework for three reason。
Firstly,to do some housework can make you independent。You can’t depend on others all your life。So,you should learn to do some housework now。
Secondly, to do some housework can keep you healthy and strong ,some hard housework can be regarded as a kind of physical exercise。
Finally, to do some housework can share your parents’ work 。They must be happy if you say” Have a rest ,and I will do the housework”
So I think it is good for students to do some housework。
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