题干

如图所示,A﹣G是初中化学常见的物质,通常情况下,A、B、G为黑色粉末状固体,D、F为红色固体,C、E为无色气体,C是绿色植物进行光合作用的一种原料,G是目前年产量最高的金属,它们之间相互转化的关系如图所示(图中部分反应物或生成物已省略),回答:

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同类题3

阅读下列短文,根据短文内容,从短文后各题所给的A、B、C、 D四个选项中,选择最佳选项。

How to Be a Better Student

    Maybe you are a common student. You probably think you will never be a top student. This is not necessary so, however. Anyone can become a better student if he or she wants to. Here's how:

Plan your time carefully. When you plan your week, you should make a list of things that you have to do. After making this list, you should make a schedule of your time. First set your time for eating, sleeping, dressing, etc. Then decide a good, regular time for studying. Don't forget to set aside enough time for entertainment. A weekly schedule may not solve all your problems, but it will force you to realize what is happening to your time.

    Find a good place to study. Look around the house for a good study area. Keep this space, which may be a desk or simply a corner of your room, free of everything but study materials. No games, radios, or television! When you sit down to study, concentrate on the subject.

    Make good use of your time in class. Take advantage of class time to listen to everything the teachers say. Really listening in class means less work later. Taking notes will help you remember what the teacher says.

    Study regularly. When you get home from school, go over your notes, review the important points that your teacher is going to discuss the next day, read that material. This will help you understand the next class. If you do these things regularly, the material will become more meaningful, and you will remember it longer.

    Develop a good attitude about tests. The purpose of a test is to show what you have learned about a subject. They help you remember your new knowledge. The world won't end if you don't pass a test, so don't be over worried.

    There are other methods that might help you with your studying. You will probably discover them after you have tried these. 

同类题4

阅读下文,完成下列各题。

白手起家,不能手无寸铁

鲁先圣

    ①我们常常说,“人可以白手起家,但不能手无寸铁”。这里的“铁”,就是一个人立身处世的资本和能耐,也可以说是你创业的本领。

    ②哈佛大学教授哈恩曼曾经这样说:即使你再羸弱、再贫穷、再普通,你仍然拥有别人羡慕的优势。对于梦想难成真的人来说,不是缺少才能,而是缺少对自己才能的发现,缺少对自己人生价值的开发利用。

    ③美国人马克•吐温作为职业作家和演说家,在文学领域和演说领域取得了极大的成功,成为世界范围内受人尊敬的文学和演说大师。但是,在他选择文学和演说之前,他曾经试图成为一名商人。他先是投资开发打印机,花费了整整3年的时间,最后把千辛万苦借来的5万美元全部赔光了。他又发现出版商因为发行他的著作而赚了大钱。他很不服气,心想,我自己写了文章自己出版发行,所有的利润不都是自己的吗?为何不自己开一个出版公司呢?他于是又投资开了一家出版公司。但是,他不知道,写作与经商是截然不同的两回事,他很快就因为债务陷入了困境,出版公司破产了,他也陷入了更大的债务危机当中。

    ④经过两次经商失败的打击,马克•吐温终于认识到自己经商的无能,他彻底断绝了经商的念头。痛定思痛,他发现自己没有找到自己的强项,自己有写作和演讲的才能,而自己却没有很好地使用。到全国巡回演讲,在演讲的间隙里埋头写作。很快,风趣幽默的马克•吐温声名大噪,成为全国知名的演说家,脍炙人口的作品也迅速走红。

    ⑤美国政治家富兰克林说:“宝贝放错了地方就是废物。”马克•吐温开始经商的经历就是把宝贝放错了地方。尺有所短,寸有所长。你也许兴趣广泛,掌握多种技能,但是,在所有的长处中,总是有你的强项。成功者的原则是:去选择最能够使自己全力以赴的、最能够使自己的品格和长处得以充分发挥的职业。因为,唯有充分利用了自己的长处,才能够让自己的人生增值;相反,你总是选择自己的短处,你的人生就只能贬值了。

    ⑥很显然,一个人的成功,来自于对自己优势的发现,来自于对自己所从事的事业的专注和投入,来自于对自己事业的无怨无悔!而这些,正是一个成功者必备的人生之“铁”。

    ⑦当你发现培养了自己的手中之“铁”的时候,等待你去采摘的,都是人生甘甜的果实。

(选自《意林》2011第5期)