课后限时作业8.doc

课后限时作业(八)
限时/50分钟
Ⅰ.阅读理解
Plants are flowering faster than scientists predicted in reaction to climate change, which could have long damaging effects on food chains and ecosystems.
Global warming is having a great effect on hundreds of plant and animal species around the world, changing some living patterns, scientists say.
Increased carbon dioxide (CO2) in the air from burning coal and oil can have an effect on how plants produce oxygen, while higher temperatures and changeable rainfall patterns can change their patterns of growth.
“Predicting species' reaction to climate change is a major challenge in ecology，” said the researches of several U．S. universities. They said plants had been the key object of study because their reaction to climate change could have an effect on food chains and ecosystem services.
The study, published on the Nature website, uses the findings from plant life cycle studies and experiments across four continents and 1,634 species. It found that some experiments had underestimated(低估) the speed of flowering by 8.5 times and leafing by 4 times.
“Across all species, the experiments under­predicted the speed of the advance—for both leafing and flowering—that results from temperature increases，” the study said.
The design of future experiments may need to be improved to better predict how plants will react to climate change, it said.
Plants are necessary for life on the Earth. They are the base of the food chain, using photosynthesis(光合作用)to produce sugar from carbon dioxide and water. They let out oxygen which is needed by nearly every organism on the planet.
Scientists believe the world's average temperature has risen by about 0.8℃ since 1900, and nearly 0.2℃ every ten years since 1979.
So far, efforts to cut emissions(排放) of planet­warming greenhouse gases are not seen as enough to prevent the Earth heating up beyond 2℃ this century—a point scientists say will bring the danger of a changeable climate in which weather extremes are common, leading to drought, floods, crop failures and rising sea levels.
语篇导读
本文为说明文，介绍了全球变暖的气候环境会让植物提前生长开花，进而影响整个食物链及生态系统。
1．What is the key information the author wants to give in Paragraph 1?
A．Plants' reaction to weather could have damaging effects on ecosystem.
B．The increasing speed of flowering is beyond scientists' expectation.
C．Climate change leads to the change of food production patterns.
D．Food chains have been seriously damaged because of weather.
解析 B　细节理解题。根据第一段可知，作者是要告知读者植物开花的增速超出了科学家的预期，故选B项。
2．What can we learn from the study published on the Nature website?
A．Plants' flowering is 8.5 times faster than leafing.
B．There are 1,634 plant species on the four continents.
C．Scientists should improve the design of their experiments.
D．The experiments failed to predict how plants react to climate change.
解析 C　推理判断题。根据第五段第二句可推出，对于植物所设计的实验应该有所改进，故选C项。
3．Why do scientists pay special attention to the study of plants?
A．Because they can prove the climate change clearly.
B．Because they are very important in the food chains.
C．Because they play a leading role in reducing global warming.
D．Because they are growing and flowering much faster than before.
解析 B　细节理解题。根据第四段第二句可知，植物对气候变化的反应对整个食物链和生态系统都至关重要，故选B项。
4．What can be inferred from the last two paragraphs about the world's temperature?
A．It has risen nearly 0.2℃ since 1979.
B．Its change will lead to weather extremes.
C．It is 0.8℃ higher in 1979 than that of 1990.
D．The rise of the temperature needs to be controlled within 2℃ in this century.
解析 D　推理判断题。根据最后一段可知，如果本世纪地球变暖超过2℃，便会出现极端天气，由此可推出，这个世纪地球温度的上升需要控制在2℃的范围之内，故选D项。
Ⅱ.完形填空
There was once a little grey planet. It was very 1 . The people living there hadn't looked after it, though they had all the 2 you could ever need because of the rapid development of technology.They had polluted the whole planet so seriously with 3 that there were no plants or wild animals 4 .
One day, a little boy was walking on the planet when he passed a cave and 5 a small red flower inside.The flower was very 6 almost dying, so the boy 7 dug up the flower with roots, soil and everything.Then he started 8 a place where he could look after it.He searched all over the planet, but everywhere was so 9 that there was no place for the flower to live.Then he looked up at the 10 and saw the moon.“Maybe the flower can 11 there，” thought the boy. 12 the little boy put on his astronaut suit, and climbed into a 13 . He put the little red flower in the back, and they went to the moon.
Far from all that pollution, the flower started to 14 . The flower was so 15 cared for that it started producing seeds soon, 16 others.Before long, flowers completely 17 the moon, which looked very 18 . The earth on which we live has also been 19 in a very bad way.If we don't look after it, maybe someday we will also only be able to plant flowers on the moon.Do you want that day to 20 ？
1．A.moved　　　　　　　　　　 B．sad
C．surprised D．pretty
2．A.food B．space
C．inventions D．skills
3．A.air B．water
C．smoke D．rubbish
4．A.needed B．stored
C．protected D．left
5．A.picked B．threw
C．noticed D．tasted
6．A.sick B．lucky
C．fresh D．strange
7．A.suddenly B．carefully
C．easily D．hopefully
8．A.taking over B．looking through
C．making up D．looking for
9．A.dirty B．wet
C．deep D．quiet
10．A.land B．mountain
C．forest D．sky
11．A.stay B．survive
C．fight D．love
12．A.So B．But
C．Because D．Once
13．A.boat B．car
C．spaceship D．train
14．A.shine B．argue
C．grow D．stand
15．A.calmly B．well
C．gradually D．normally
16．A.giving birth to B．taking care of
C．looking down upon D．taking control of
17．A.cleaned B．admired
C．covered D．destroyed
18．A.wide B．round
C．bright D．beautiful
19．A.supported B．polluted
C．divided D．hidden
20．A.return B．disappear
C．come D．develop
语篇导读
本文为一则童话故事，告诫我们要保护环境、爱护地球。
1．解析 B　根据下文的描述可知，那个星球污染非常严重，可推断那个星球很伤心(sad)，故选B项。
2．解析 C　根据空后的because of the rapid development of technology可推知，此处是指那个星球上的发明(invention)，故选C项。
3．解析 D　他们把那个星球严重地污染了，污染环境的应该是垃圾(rubbish)，故选D项。
4．解析 D　星球已被污染，所以植物和野生动物都无法存活了，也就是说任何的野生动植物都没有被留下(leave)，故选D项。
5．解析 C　根据语境可知，此处是指男孩经过一个洞的时候，看到(notice)了洞里的一朵花，故选C项。
6．解析 A　根据空后的almost dying可知，小花病得厉害，sick符合语境，故选A项。
7．解析 B　小花就快死了，小男孩应该是非常小心地(carefully)把它挖出来，故选B项。
8．解析 D　根据语境可知，小男孩想找个地方把小花重新栽种，以便照顾它。take over接管；look through看穿，游览；make up编造，弥补，化妆；look for寻找，故选D项。
9．解析 A　根据上文可知，那个星球上到处都很脏(dirty)，故选A项。
10．解析 D　根据小男孩看到了月亮可知，他抬头看天空(sky)，故选D项。
11．解析 B　根据语境可知，小男孩心想或许小花可以在月亮上存活(survive)，故选B项。
12．解析 A　小男孩心想或许小花可以在月亮上存活，所以(so)他准备去月球，故选A项。
13．解析 C　小男孩要去月球，所以他穿上航空服，登上了宇宙飞船(spaceship)，故选C项。
14．解析 C　到了月球上，环境变好了，小花开始生长(grow)，故选C项。
15．解析 B　根据下文的it started producing seeds soon可知，小花被照顾得很好(well)，故选B项。
16．解析 A　根据语境可知，此处讲的是小花开始繁衍，giving birth to繁殖；take care of照顾；look down看不起；take control of控制，故选A项。
17．解析 C　小花迅速繁衍，很快就覆盖(cover)了整个月球，故选C项。
18．解析 D　月球被花儿覆盖了，看起来非常漂亮(beautiful)，故选D项。
19．解析 B　此处是指我们的地球也被很严重地污染(pollute)了，故选B项。
20．解析 C　地球也被很严重地污染了，或许有一天我们也只能在月球上种花了，作者问我们：真的希望那一天到来(come)吗？，故选C项。
Ⅲ.语法填空
Throughout history, the Chinese nation has constructed 1. (thousand)of magnificent bridges, 2. ， of course, have become one of the marks of ancient Chinese civilization.
The Guangji Bridge, 3. (know) as the first opening bridge in the world, is one good example of them. It 4. (lie) in the eastern suburb of Chaozhou, China, across the Han River for over 800 years, which at first was 5. (simple) a boat bridge built in 1170 A．D. in Southern Song Dynasty with the 6. (long) of 518 meters.Later construction of piers and framework started from both banks of the river on which it was fixed, and it took a total of 200 years 7. (complete) the Guangji Bridge with a floating section of 18 supporting wooden boats in between the two beamed sections. When necessary, the floating section can be unlocked for the passage of big boats, which is really 8. imaginative invention in bridge­building history. There are two iron cows standing at both ends of the bridge, 9. the hope of protecting the bridge from the flood damage. 10. makes the bridge particularly outstanding is that its two beamed sections resemble waterside streets with 24 different style's pavilions and towers for doing business, which become a special view on the bridge.
语篇导读
本文为说明文。在历史上，中华民族曾经建造了许多壮丽的桥梁，这些桥梁是中国古代文明的标志。其中位于潮州的广济桥就是一个典型代表。
1．thousands　解析 考查固定搭配。句意：在历史上，中华民族曾经建造了成千上万座壮丽的桥梁，当然，这些桥梁已成为中国古代文明的标志之一。thousands of数以千计的。
2．which　解析 考查引导词。分析句子结构可知，空处引导非限制性定语从句，修饰先行词bridges, 从句中缺少主语，故填which。
3．known　解析 考查非谓语动词。分析句子结构可知，句中已有谓语，此处应用非谓语动词形式；know与逻辑主语The Guangji Bridge之间是动宾关系，故用过去分词known作后置定语。
4．lies　解析 考查时态和主谓一致。主语It是单数，而且描述的是一般事实，故用一般现在时。
5．simply　解析 考查词性转换。空处在句中作状语，应用副词，故填simply(仅仅；只不过)。
6．length　解析 考查词性转换。空前为定冠词，空后为介词，因此空处应用名词。
7．to complete　解析 考查非谓语动词。此处为“It takes/took (sb) some time to do sth”结构，it作形式主语，真正的主语是后面的动词不定式。
8．an　解析 考查冠词。此处泛指“一项发明”，且imaginative以元音音素开头，故填不定冠词an。
9．in　解析 考查介词。句意：桥头两端分立两头铁牛，人们期望它们保护广济桥免受洪水的侵害。in the hope of怀着……的希望。
10．What　解析 考查引导词。分析句子结构可知，空处引导主语从句，且在从句中作主语，指物，故填What。
Ⅳ.应用文写作
假如你是李华，是某国外英语学习网站的注册会员，但最近在使用网站时发现一些不太满意的地方，因此，你向网站负责人Smith先生写一封投诉信，内容包括：1.投诉原因；2.提出希望。
注意：1.80词左右；
2．可适当增加细节，以使行文连贯。
【参考范文】
Dear Mr Smith，
I've recently signed up for your English learning website. However, I have come across some problems after using it for a short time. I'm writing to make a complaint about them.
To begin with, some contents cannot be updated in time, which makes it impossible for me to learn something new related to my present lessons at school. Much to my dissatisfaction, I find the topics of some reading materials are not proper for us middle school students. As a famous website, your service needs improving to live up to users' expectations. I hope you can take the matter seriously and make an effort to solve the problems.
Looking forward to your prompt reply.
Yours respectfully，
Li Hua