阅读理解

    There are about fifteen hundred languages in the world. But only a few of them are very important. English is one of them. Many, many people use it, not only in England and the USA, but also in other parts of the world. About 200, 000, 000 people speak it as their own language. It is difficult to say how many people are learning it as a foreign language. Millions of people are trying to do so. Is it easy or difficult to learn English? Different people may have different answers. Have you ever noticed ads(广告) of this kind in the newspapers or magazines? "Learn English in six weeks, or give your money back. . . " "Easy and funny. . . " "Our records and tapes help you master English in a month."Of course, it never happened quite like that.  　　

    The only language that seems easy to learn is the mother tongue. We should remember that we all learned our own language well when we were children. If we could learn English in the same way, it would not seem so difficult. Think of what a small child does. He listens to what people say. He tries what he hears. So it is hard to say that learning English is easy. We must do a lot of practice. And practice needs great efforts(努力) and takes much time. Good teachers, records, tapes, books, and dictionaries will be helpful, but they cannot do the student's work for him.  

下列物理现象中，属于升华的是(    )

$\frac{3}{4}-\frac{3}{8}+\frac{5}{8}$ =____

下列各句中，加点的成语使用恰当的一项是（    ）

①张秘书广泛查阅资料，并对资料进行细致分析，经过一个多月的努力，终于完成了这一称得上不易之论的人事改革方案的初稿。

②虽然苏轼一直被卷入政治漩涡中，但他光风霁月，超脱于蝇营狗苟的政治斗争之外，纯然表达心之所感，将得失置之度外。

③近日，中共中央提出了要精简会议活动，切实改进会风等八项规定，此举对于长期以来习惯了好整以暇、办事疲沓的官员们，无疑是一剂良药。

④作为城里人如果错误地认为农村远离城市，对农村污染视而不见，甚至把城市污染物转移到农村，终究要自食其果，用自己的健康来偿还。

⑤2013年8月31日中华人民共和国第十二届全运会的开幕式简短而不失大气，丰富而不乏新颖，特别是辽宁12支健身队伍的涌入，使得整场演出精彩纷呈，美轮美奂。

⑥机器能够为人类造福，但如果将来机器发展得足够智能，那么人工智能就是“人类最大的潜在威胁”，玩弄人工智能等同于“召唤恶魔”， 玩火自焚。