日本成人片在线_久久免费精品视频_国产午夜精品久久久久久免费视_校花撩起jk露出白色内裤国产精品_av影片免费在线观看_国产小视频在线看_最新av免费在线观看_99久久99久久精品国产片_欧美成人猛片aaaaaaa_蜜桃免费网站一区二区三区

精英家教網 > 高中英語 > 題目詳情

The earth ________ to be flat.


  1. A.
    was used to be thought
  2. B.
    used to be thought
  3. C.
    was used to think
  4. D.
    used to think
B
解析:
be used to doing指“習慣于”;be used to do指“被用來做”;used to do指“曾經,(以前)常常”。而本句后的to be flat作think的賓語補足語。
練習冊系列答案
相關習題

科目:高中英語 來源:2012屆重慶市渝北中學高三(上)第三次月考英語試卷 題型:閱讀理解

LONDON: What could possibly be wrong with planting trees? The benefits are obvious; they  firm the soil, soak up (攝取) extra water and take carbon dioxide (二氧化碳) out of the atmosphere.
However, it now turns out that planting trees could add to global warming.
Tree roots do a great job of keeping soil firmly on the ground and out of the wind’s power. The problem is that some of those dust clouds play an important part in taking in carbon dioxide.
Huge dust storms blow out over the oceans from dry parts of North Africa and central Asia. Tons of dust are lifted and left as a thin film over the ocean surface. The dust fuels oceanic life.
Dust from China is carried east and left in the Pacific Ocean. If a tree-planting programme there is successful and the dust supply reduced, the final result may be that less carbon dioxide gets locked away in the ocean.
Andy Ridgwell, an environmental scientist from the University of East Anglia, has spent the past few years studying dust and says his work “shows clearly the complexity of the system and the importance of not tinkering(粗劣地修補) with it without understanding the results. For this reason the need is to focus(集中) on cutting carbon dioxide giving off rather than monkeying (瞎弄) about with the land surface.”
An American scientist, Robert Jackson, has shown that when native grassland areas are invaded(侵入) by trees, carbon is lost from the soil. “We are studying why the soil carbon disappears, but one theory is that trees do a lot more of their growing above ground compared to grasses, so less carbon goes directly into the soil from trees, ” says Jackson.
In wet areas of the world, the gain from trees absorbing carbon dioxide above ground seems to be outweighed(超過) by the loss of carbon from the soil below ground. Countries that plan to combat global warming by planting trees may have to think again.
Solutions to environmental problems are often more complex than they first appear, and understanding the Earth’s climate is a very great challenge.
【小題1】People usually hold the opinion that_____________.

A.huge dust storms can destroy carbon dioxide
B.huge dust storms can destroy the oceans on the earth
C.huge dust storms can’t do anything beneficial for man
D.planting trees is the only way to control huge dust storms
【小題2】 Andy Ridgwell, the environmental scientist, believes that_____________.
A.dust plays a more important part than trees
B.trees shouldn’t have been planted in dry places
C.carbon dioxide is harmful to everything on the earth
D.environmental problems are more complex than expected
【小題3】 Robert Jackson’s experiment proves that_____________.
A.grassland areas should be covered by forests
B.trees hold more carbon than grasses
C.carbon can turn grass into dust
D.less carbon can make trees grow faster

查看答案和解析>>

科目:高中英語 來源:2012-2013學年江西省高安中學高一上學期期末考試英語試卷(帶解析) 題型:閱讀理解

Most earthquakes occur within the upper 15 miles of the earth’s surface, but earthquakes can and do occur at all depths to about 460 miles. Their number decreases as the depth increases. At about 460 miles one earthquake occurs only every few years. Near the surface earthquakes may run as high as 100 in a month, but the yearly average does not vary much.
The extent of the disaster in an earthquake depends on many factors. If you carefully build a toy house with an erect set (堅立架), it will still stand no matter how much you shake the table. But if you build a toy house with a pack of cards, a slight shake of the table will make it fall. An earthquake in Agadir was not strong, but it completely destroyed the city. Many stronger earthquakes have done comparatively little damage. If a building is well constructed and built on solid ground, it will resist an earthquake. Most deaths in earthquakes have been due to faulty building construction or poor building sites. A third and very serious factor is panic. When people rush out into narrow streets, more deaths will result.
There is one type of earthquake disaster that little can be done about. This is the disaster caused by seismic (地震的) sea waves, or tsunamis (海嘯). These are often called tidal waves, but the name is incorrect. They had nothing to do with tides. In certain areas, earthquakes take place beneath the sea. These submarine earthquakes sometimes give rise to seismic sea waves. The waves are not noticeable out at sea because of their long wave length. But when they roll into harbors, they pile up into walls of water 6 to 60 feet high. The Japanese call them “tsunamis” meaning “harbor waves”, because they reach a sizable (相當大的) height only in harbors.
Tsunamis travel fairly slowly, at speeds up to 500 miles an hour. An earthquake warning system is in use to warn all shores likely to be reached by the waves. But this only enables people to leave the threatened shores for higher ground: There is no way to stop the oncoming wave.
【小題1】Which of the following can NOT be concluded from the passage?

A.The number of earthquakes is closely related to the depth.
B.Roughly the same number of earthquakes occur each year.
C.Earthquakes are impossible at depths over 460 miles.
D.Earthquakes are most likely to occur near the surface.
【小題2】The destruction of Agadir is an example of       .
A.faulty building construction
B.an earthquake’s strength
C.widespread panic in earthquakes
D.ineffective instruments
【小題3】According to the passage, the waves caused by submarine earthquakes are not noticeable out at sea because of       .
A.their high speed
B.the wide shores
C.their silent movements
D.their long wave length
【小題4】The significance of the slow speed of tsunamis is that people may      .
A.help reduce fear
B.find ways to stop them
C.be warned early enough
D.develop warning systems
【小題5】According to the passage, the number of factors that may determine the extent of the disaster in an earthquake is      .
A.two B.fiveC.four D.three

查看答案和解析>>

科目:高中英語 來源:2012-2013學年內蒙古包頭三十三中高二上學期期中考試英語試卷(帶解析) 題型:閱讀理解

Will life in the future be better, worse or the same as now? Futurologists(未來學家)predict that life will probably be very different in 2050.
First of all, it seems that TV channels will have disappeared by 2050. A computer will send the program directly to the television. On TV screen appear holograms(全息圖), which are pictures with certain height, width and depth. We will be able to see, smell and touch the things that we see on television.
Water has become one of our most serious problems. Agriculture is changing and people are growing more fruit and vegetables to export. Demand for water will increase ten times in 2050. Some futurologists predict that water will be the cause of war if we don’t act now.
In transport, cars will run on new fuels and go very fast. A car will have computers to control its speed and there won’t be any accidents. On the other hand, space planes will take people around the earth in about three hours. People will fly from Los Angeles to Tokyo by space plane in just half an hour.
In the field of technology, robots will have replaced people in factories. By 2050, we will see robots everywhere. They do not ask for pay rises or go on strike, and they work 24 hours a day. 
Medicine technology will have conquered many diseases by 2050; we will be able to help blind and deaf people see again and hear again. Scientists have discovered how to control genes. They have already produced clones of animals and will be able to produce clones of people and decide how they look, how they behave and how much intelligence they have. If you want all this to come true, you should study science and technology hard.
【小題1】What is the main difference between today’s and 2050’s TV?

A.We can use a computer to turn off the TV set.
B.We can talk with the characters appearing on TV.
C.We can choose whatever we like to see on TV.
D.We can touch the things we see on TV.
【小題2】What isn’t mentioned about the future in 2050 in the passage?
A.Technology.B.Medicine.C.Movies.D.Agriculture.
【小題3】What will be more likely to cause the war in the future?
A.The lack of water. B.The less farmland.
C.The shortage of robots.D.The more space planes.
【小題4】From the passage we can infer that by 2050 ____.
A.people will spend less time in studying
B.more and more people needn’t go to school
C.people will have more time to relax or rest
D.no patients will be found in the world

查看答案和解析>>

科目:高中英語 來源:2011屆湖北省武漢市武昌區高三上學期元月調研測試英語卷 題型:閱讀理解

Scientists who try to predict earthquakes have gotten some new helpers recently—animals.
  That’s right, animals. Scientists have begun to understand what farmers have known for thousands of years. Animals often seem to know in advance that an earthquake is coming, and they show their fear by acting in strange ways. Before a Chinese quake in 1975, snakes awoke from their winter sleep early only to freeze to death in the cold air. Cows broke their halters (韁繩) and tried to escape. Chickens refused to enter their cage. All of this unusual behavior, as well as physical changes in the earth, warned Chinese scientists of the coming quake. They moved people away from the danger zone and saved thousands of lives.
  One task for scientists today is to learn exactly which types of animal behavior predict quakes. It’s not an easy job. First of all not every animal reacts to the danger of an earthquake. Just before a California quake in 1977, for example, an Arabian horse became very nervous and tried to break out of his enclosure. The Australian horse next to him, however, remained perfectly calm. It’s also difficult at times to tell the difference between normal animal restlessness and “earthquake nerves”. A zoo keeper once called earthquake researchers to say that his cougar had been acting strangely. It turned out that the cat had an upset stomach.
  A second task for scientists is to find out exactly what kind of warnings the animals receive. They know that animals sense far more of the world than humans do. Many animals can see, hear, and smell things that people do not even notice. Some can sense tiny changes in air pressure, gravity, or the magnetism of Earth. This extra sense probably helps animals predict quakes.
  A good example of this occurred with a group of dogs. They were shut in an area that was being shaken by a series of tiny earthquakes. (Several small quakes often come before or after a large one.) Before each quake a low booming sound was heard. Each boom caused the dogs to bark wildly. Then the dogs began to bark during a silent period. A scientist who was recording quakes looked at his machine. It was acting as though there were a loud noise too. The scientist realized that the dogs had reacted to a booming noise. They also sensed the tiny quake that followed it. The machine recorded both, though humans felt and heard nothing.
In this case there was a machine to monitor what the dogs were sensing. Many times, however, our machines record nothing extraordinary, even though animals know a quake is coming. The animals might be sensing something we measure but do not recognize as a warning. Discovering what animals sense, and learning how they know it is a danger signal, is a job for future scientists.
【小題1】Through the passage the writer hopes to explore __________.

A.why animals send a danger signal before an earthquake
B.how animals know when an earthquake is coming
C.why animals not men have good sense of danger
D.how much animals know about an earthquake
【小題2】 During an earthquake in China in 1975, _________.
A.chickens refused to go out of their cage
B.snakes were frozen to death in their caves
C.snakes awoke from their winter sleep earlier
D.cows broke their halters and escaped from their sheds
【小題3】Which of the following is one of earthquake nerves according to the passage?
A.An Arabian horse tried to escape from his enclosure.
B.A cougar had an upset stomach unexpectedly.
C.An Australian horse was perfectly calm.
D.A cat acted very strangely in a zoo.
【小題4】The scientists did an experiment with a group of dogs to _________.
A.find out that the machine could record unusual happenings
B.compare the reactions of animals and those of humans
C.prove that animals could sense more than humans
D.find out what exact warnings animals sent

查看答案和解析>>

科目:高中英語 來源:2010年長春外國語學校高一下學期期末考試英語卷 題型:填空題

單詞拼寫(共10小題;每小題1分,滿分10分)
61. Yuan Longping is quite s_______ ( 滿意的 )with his life.
62. Dr Yuan searched for a way to increase rice harvest without e______ (伸展,使變大)the area of the fields.
63. She spent her life c______ (參加運動)for women’s rights.
64. I love roast pork and f______ rice (炒飯)
65. You must ask for p______(允許) before taking pictures in the church.
66. She was so afraid of being laughed at by her friends that she did not c______(咨詢) a doctor.
67. We missed the first few s______ (幕, 場) of the play because we were caught in the heavy rain.
68. Dinosaurs laid eggs too and e______ (存在)on the earth for more than 140 million years.
69. Swap summaries with your partner and give each other  c_______(評論).
70. It is so wet there that the trees are extremely tall, some m______(測量) over 90 meters.                                    

查看答案和解析>>

同步練習冊答案
国产一区二区三区四区福利| 欧美高清视频一区二区三区| 国产高清精品在线观看| 相泽南亚洲一区二区在线播放| 国产欧洲精品视频| 日本欧美国产在线| 国产做受69高潮| 九九久久久久99精品| 亚洲午夜未删减在线观看 | 亚洲精品成人悠悠色影视| 91首页免费视频| 国产精品综合二区| 久久精品国产成人一区二区三区 | 色婷婷综合久久久中文字幕| 亚洲成人av免费| 亚洲黄一区二区三区| 中文字幕一区二区三区四区不卡| 久久亚洲影视婷婷| 久久久久久久综合色一本| 91丝袜呻吟高潮美腿白嫩在线观看| 国产乱码字幕精品高清av| 麻豆精品一二三| 精品在线观看视频| 国内成+人亚洲+欧美+综合在线| 免费成人美女在线观看.| 日韩精品福利网| 免费在线观看精品| 久久97超碰色| 成熟亚洲日本毛茸茸凸凹| 成人性色生活片免费看爆迷你毛片| 国产精品亚洲一区二区三区妖精| 国产成人精品综合在线观看| 国产成人在线视频网址| 成人av高清在线| 久久精品日产第一区二区三区高清版 | 亚洲国产日韩av| 婷婷综合五月天| 色悠悠亚洲一区二区| 91久久久免费一区二区| 欧美精品乱人伦久久久久久| 日韩精品自拍偷拍| 亚洲欧美中文日韩在线| 色噜噜狠狠色综合网图区 | 久久久久久久极品内射| 国产 日韩 欧美 在线| 青娱乐在线免费视频| 91久久精品国产91性色69| 精品人妻一区二区三区三区四区 | 人人干视频在线| 亚洲国产精品毛片av不卡在线| 亚洲一区日韩精品| 亚洲国产精品无码久久久久高潮| 日韩精品电影一区二区三区| 日本少妇bbwbbw精品| 中文字幕在线观看精品| 免费观看成年人视频| 天堂资源中文在线| av文字幕在线观看| 亚洲伦乱视频| 亚洲黄页网站| 99精品热6080yy久久| 九一九一国产精品| 久久久激情视频| 亚洲永久免费av| 69堂成人精品免费视频| 亚洲人成网在线播放| 亚洲 日韩 国产第一| 91久久精品www人人做人人爽| 欧美精品一区二区三区在线四季 | 成人精品一区二区三区四区 | 欧美福利视频网站| 91免费电影网站| 日韩精品极品视频在线观看免费| 日本a在线免费观看| 俄罗斯女人裸体性做爰| 亚洲精品一区二区三区在线播放| 国产suv精品一区二区33| 人妻91麻豆一区二区三区| 在线看黄色av| 免费成人高清在线视频| 日韩精品久久久久久久电影99爱| 日韩福利视频网| 久久色中文字幕| 欧美小视频在线| 精品偷拍各种wc美女嘘嘘| 亚州av一区二区| 免费观看国产成人| 粗暴91大变态调教| 无码人妻精品一区二区中文| 亚洲成人av网址| 蜜桃免费在线| 成人在线不卡| 一区二区影院| 99久久久无码国产精品| 欧美性猛交xxxx乱大交| 亚洲午夜久久久久久久| 91精品视频观看| 日本福利视频一区| 亚洲a v网站| 国产特级黄色片| 动漫一区在线| 婷婷综合成人| 久久66热re国产| 亚洲午夜成aⅴ人片| 亚洲天堂免费视频| 成人午夜在线影院| 国产精品网站免费| a资源在线观看| 成人免费公开视频| 三妻四妾的电影电视剧在线观看| 日韩欧美午夜| av亚洲精华国产精华| 欧美中文字幕亚洲一区二区va在线 | 女人香蕉久久**毛片精品| www.亚洲色图.com| 欧美精品久久天天躁| 孩xxxx性bbbb欧美| 一区二区三区三区在线| 亚洲激情 欧美| 国产免费无遮挡| 超碰91在线观看| 66国产精品| 欧美国产日韩在线观看| 亚洲а∨天堂久久精品喷水| 成人午夜高潮视频| 波多结衣在线观看| 久热这里只有精品6| 91吃瓜网在线观看| 国产成人手机高清在线观看网站| 国产成人精品影视| 欧美日韩国产首页| 国产九九精品视频| 99视频精品免费| 在线观看黄网站| 成人看片免费| 亚洲国产不卡| 亚洲日本在线天堂| 久久精品2019中文字幕| 一区二区三区观看| 无码人妻丰满熟妇啪啪欧美| 一本到av在线| 免费看久久久| 26uuu国产在线精品一区二区| 日韩欧美亚洲一区二区| 91九色蝌蚪成人| 亚洲黄色小说在线观看| 亚洲精品国产一区二| 国产999精品在线观看| 美女视频黄a大片欧美| 欧美色成人综合| 国产精品视频男人的天堂| 老司机午夜av| 国产精品乱码久久久| 91精品国产66| 国产一区二区美女诱惑| 欧美不卡一区二区| 国产一区二区三区免费不卡| 精品国产人妻一区二区三区| 免费观看v片在线观看| 欧美在线导航| 日本一区二区三区四区| 少妇精69xxtheporn| 一二三四中文字幕| 天天操中文字幕| 涩涩网在线视频| 麻豆91精品视频| 欧美大片在线观看一区二区| 国产一区二区三区黄| 亚洲色图日韩精品| 黄在线免费观看| 亚洲精一区二区三区| 一本大道久久a久久精二百| 国产精品中文在线| 91精品人妻一区二区三区蜜桃2| 亚洲av片在线观看| 视频一区欧美| 一区二区三区四区不卡视频| 日韩av免费在线观看| 欧美精品 - 色网| 黄色小视频在线播放| 国产精品三级| 亚洲国产wwwccc36天堂| 国产日韩欧美电影在线观看| 少妇精品无码一区二区三区| 日韩偷拍自拍| 国语自产精品视频在线看8查询8| 一本久道中文字幕精品亚洲嫩| 91在线免费看网站| a级在线免费观看| av网站导航在线观看免费| 天堂va蜜桃一区二区三区漫画版| 欧美一区二区三区视频在线| 日本一区免费在线观看| 久久精品这里有| 黄色精品视频网站| 久久影院视频免费| 欧美亚洲另类制服自拍| 稀缺小u女呦精品呦| av午夜在线| 日韩精品五月天| 亚洲精品小视频在线观看| 奇米777四色影视在线看| 一二三区在线播放| 亚洲精品播放| 狠狠操狠狠色综合网| 国产视频在线观看一区| 国产一级在线视频| 国产高清亚洲| 亚洲欧美激情一区二区| 91在线播放国产| 波多野结衣在线网址| 免费高清视频在线一区| 国产午夜亚洲精品羞羞网站| 欧美在线视频a| 国产真实乱人偷精品人妻| 国产精品探花在线| 成人av网站大全| 国产999精品视频| wwwww黄色| 成人日韩精品| 国产精品久久福利| 成人在线精品视频| 妺妺窝人体色www聚色窝仙踪| 成人午夜毛片| 亚洲综合另类小说| 国产自产精品| 亚洲午夜在线播放| 色无极亚洲影院| 精品国产一区二区三区久久影院| 国产精品网站免费| 日本亚洲一区| 国产一区二区三区四区五区入口 | 九色网友自拍视频手机在线| 日本中文字幕一区| 九九九热精品免费视频观看网站| 污污污www精品国产网站| av免费在线视| 国产婷婷色一区二区三区在线| 国产欧美一区二区| 日本天堂在线视频| 精品在线播放| 日韩三级高清在线| 色婷婷综合久久久久中文字幕| 电影av一区| 成a人片亚洲日本久久| 国产精品视频男人的天堂| 豆国产97在线 | 亚洲| 美日韩黄色大片| 欧美一区三区二区| 精品免费国产一区二区| 美女国产在线| 久久久777精品电影网影网| 亚洲伊人一本大道中文字幕| 毛片视频网站在线观看| 日韩国产在线| 精品亚洲一区二区三区在线观看| 男生操女生视频在线观看 | 日韩电影在线免费| 久久久久五月天| 日本伦理一区二区三区| 成人香蕉社区| 精品少妇一区二区三区视频免付费 | 蜜臀av一区| 欧美xxx久久| 亚洲国产欧美91| 成人日韩在线观看| 欧美三级xxx| 成人免费观看cn| 国产日产一区二区| 日韩美女久久久| 亚洲视频小说| 国产三级视频在线| 国产亚洲综合色| 日韩高清av| 日韩电影在线观看完整版| jiyouzz国产精品久久| 99re视频在线播放| 精品国产av鲁一鲁一区| 欧美aⅴ一区二区三区视频| 国产精品美女网站| 日本三级一区二区三区| 日韩视频在线一区二区三区 | 亚洲一区二区三区xxx视频| 在线观看中文字幕2021| 丝袜美腿成人在线| 国产精品视频久久久| 国产精品福利电影| 久久精品国产免费| 亚洲自拍在线观看| 理论片中文字幕| 成人午夜视频在线| 欧美凹凸一区二区三区视频| 香蕉网站在线观看| 欧美国产1区2区| 99亚洲精品视频| 麻豆网站在线免费观看| 亚洲精品久久久蜜桃| 男人用嘴添女人下身免费视频| 好久没做在线观看| 在线免费亚洲电影| 五月天国产视频| 少妇精品在线| 亚洲精品在线看| 女同久久另类69精品国产| 婷婷综合激情| 91av国产在线| 97人妻精品一区二区三区动漫| 久久国产精品色| 久久大香伊蕉在人线观看热2| 有码在线播放| 亚洲另类一区二区| 国产天堂在线播放| 四虎在线精品| 亚洲男人天堂久| 校园春色 亚洲| 国产精品美女久久久浪潮软件| 成人黄色片在线| 最近最好的中文字幕2019免费 | 亚洲成人一区在线| 岛国毛片在线播放| 成人中文字幕视频| 久久精品成人一区二区三区| 日韩一级在线视频| 狠狠狠色丁香婷婷综合激情 | 另类欧美日韩国产在线| 精品一区二区不卡| 99青草视频在线播放视| 色综合色综合色综合| 韩国三级与黑人| 欧美在线色图| 国产91免费看片| 午夜影院免费视频| 亚洲视频图片小说| 中文字幕22页| 午夜欧洲一区| 2019中文字幕在线观看| 免费观看国产精品| 亚洲欧美日韩国产一区二区三区 | 国产高清在线观看视频| 久久久精品国产免费观看同学| 欧美 丝袜 自拍 制服 另类| **国产精品| 欧美精品生活片| 性一交一乱一透一a级| 国产精品看片你懂得 | 成人福利av| 亚洲欧美日韩国产中文| 亚洲天堂男人av| 99久久国产综合精品色伊| 精品久久一二三| 粉嫩的18在线观看极品精品| 久久久久久成人| 少妇喷水在线观看| 亚洲午夜久久久久久久久电影网 | 欧美视频中文字幕在线| 疯狂揉花蒂控制高潮h| 伊人激情综合| 麻豆传媒一区二区| 欧美gv在线| 伊人av综合网| av综合在线观看| 一区二区三区高清不卡| 亚洲香蕉中文网| 99精品视频免费观看视频| 日韩av一区二区三区在线| 香蕉视频亚洲一级| 久久国产精品久久久久| 日本高清视频www| 婷婷综合五月天| 岛国片在线免费观看| 久久黄色级2电影| 免费看黄在线看| 偷窥自拍亚洲色图精选| 成人免费淫片aa视频免费| av免费看在线| 日韩激情片免费| 国产精品久久综合青草亚洲AV| 一区二区三区在线免费| 自拍偷拍亚洲天堂| 久久国产生活片100| 欧美网站免费观看| 国产精品片aa在线观看| 亚洲aa在线观看| 国模精品视频| 欧美裸体xxxx极品少妇| 色视频在线播放| 制服丝袜亚洲色图| 日本中文字幕在线| 亚洲欧洲成人精品av97| 国产精品1000部啪视频| 精品系列免费在线观看| 日本成人在线免费视频| 小说区亚洲自拍另类图片专区| 免费观看成人在线| 国产一区一区| 国产精品日韩久久久久| av免费在线视| 992tv成人免费视频| 9191在线观看| 中文国产亚洲喷潮|