问题 问答题

科学家在美国夏威夷的莫纳洛亚山顶设置了高精度气体分析器,对大气中二氧化碳的含量进行了连续测量,下图描述的是1958年至1994年期间的测量结果.

请你根据该图分析:

(1)莫纳洛亚山顶空气中二氧化碳的含量是怎样变化的?

(2)可能是什么原因导致了这样的变化?

(3)你认为当前自己所居住的地区空气中二氧化碳的含量随时间的变化图象可能是什么样的?(在所给的方框中画出你想象的图线,并解释为什么你画出了那样的图线.)

(4)说说看,我们的大气中二氧化碳的含量增加是利还是弊?

答案

(1)根据图象可以看出,二氧化碳的含量逐年上升,且每一年度冬天的含量高于夏天,所以本题答案为:在每一年度里,二氧化碳的含量呈现季节性的变化(冬季高,夏季低),每年一个周期.在不同的年度里,二氧化碳的含量是逐年增加的,其间略有起伏;

(2)二氧化碳含量的增高可以从化石燃料的大量使用以及绿色植物对光合作用的消耗进行分析,所以本题答案为:二氧化碳含量的周期性变化是由植物的光合作用引起的,夏季植物光合作用旺盛,冬季则比较缓慢;二氧化碳含量的逐年上升趋势可能是人类过度燃烧含碳燃料引起的(如煤、石油、天然气、木柴、秸秆等).

(3)当前所居住的地区二氧化碳的含量逐年上升,且冬天的高于夏天,所以本题答案为:二氧化碳的含量逐年上升,且冬天的高于夏天,

(4)二氧化碳能促进植物的光和作用,能引起温室效应,所以本题答案为:利,促进光合作用,弊,引起温室效应.

阅读理解

阅读理解。

     The computer makes doing schoolwork easier tor me than it was tor my mom and dad. For example,

when writing book reports and stories,I use Microsoft Word instead of a pen and paper. That way, after

my teacher edits my work, I can go back and make revisions without having to rewrite the whole thing.

And Microsoft Word has a spell check! I use it all the time.

     For English class, we're reading The Outsiders, by S. E. Hinton. As a pre-reading assignment (作业), my

teacher asked us to research teenage groups on the Intemet. I tried Google, Encarta, and Yahoo first, and

finally found an article on Time. com.

     For a geography assignment on the United States, I used Encarta to learn about the Mississippi River. I

needed to find out how deep the river is, how its widths and depths are different,what states it runs through,

and what kinds of fish live in it. I used the information to show how the geography of a country influences its

economy (经济). For example,the river's trade paths,the number of fish caught in it,and the tourists it attracts

directly influence Southemers' jobs and incomes (收入).

     I never go to the library to do research. It takes too much time. Since I live in New York City and both my

parents work,getting to the library isn't always easy. For a big assignment or research project, I used to stay

at the library to read,or sign out whatever books or magazines I needed. Now being able to find the information

in my own living room makes everything a lot simpler. Online dictionaries and encyclopedias (百科全书) also

save time.

      Sometimes, I think the computer spoils young people because it's so easy-at least physically. But

computers are not like television, which does the thinking for you. You still have to use your mind. I prefer

using a computer. Easy, fun, and fast.

1. Does the computer make doing schoolwork harder for the writer?

    ______________________________________________________

2. What does the writer use when he wr tes book reports and stories? 

    ______________________________________________________

3. How does the wr ter complete a big assignment or research project? 

     ______________________________________________________

4. What does the underlined word "spoils" mean in English? 

    ______________________________________________________

5. What's the ran idea of this passage? 

    ______________________________________________________

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