It is generally believed that Watson and Crick’s discovery about DNA was ____ beginning of _____ enormous advances in _____ field of genetics.

A. the, the, the B. /, /, the C. the, /, the D. the, the, a

練習(xí)冊系列答案
相關(guān)習(xí)題

科目：高中英語 來源：2016屆甘肅會寧第一中學(xué)高三上學(xué)期第四次月考英語試卷（解析版） 題型：七選五

根據(jù)短文內(nèi)容，選出最佳選項(xiàng)，選項(xiàng)中有兩項(xiàng)為多余選項(xiàng)。

American black bears appear in a variety of colors despite their name. In the eastern part of their range, most of these bears have shiny black fur, but in the west they grow brown, red, or even yellow coats. 1. Even in the same litter (一窩幼崽）, both brown and black furred bears may be born.

Black bears are the smallest of all American bears, ranging in length from five to six feet, weighing from three hundred to five hundred pounds. 2.

3. However, if attacked, most can climb trees and cover ground at great speeds. When angry or frightened, they are formidable(可怕的) enemies.

Black bears feed on leaves, herbs, fruit, berries, insects, fish, and even larger animals. 4.Unlike squirrels, woodchucks, and many other woodland animals, bears do not actually hibernate(冬眠). Although the bear does not eat during the winter months, sustaining itself from body fat, its temperature remains almost normal, and it breathes regularly four or five times per minute.

5. They prefer to live in caves. Baby black bears are born in January or February after a gestation(懷孕) period of six to nine months, and they stay with their mother until they are fully grown or about one and a half years old. Black bears can live as long as thirty years in the wild, and even longer in some nature reserves.

A. To the north, the black bear is actually gray or white in color.

B. Black bears mate(交配) all year round.

C. One of the most interesting characteristics of bears, including the black bear, is their winter sleep.

D. Like all bears, the black bear is timid, clumsy, and rarely dangerous.

E. Bears often eat a lot of food before they hibernate in their caves.

F. Most black bears live alone, except during mating season.

G. Their eyes and ears are small and their eyesight and hearing are not as good as their sense of smell.

查看答案和解析>>

科目：高中英語 來源：2016屆吉林長春外國語學(xué)校高三上學(xué)期第二次質(zhì)檢英語試卷（解析版） 題型：閱讀理解

In 1826, a French man named Niepce needed pictures for his business. But he was not a good artist. He invented a very simple camera. He put it in a window of his house and took a picture of his garden. That was the first photo.

The next important date in the history of photography was in 1837. That year, Daguerre, another Frenchman, took a picture of his reading room. He used a new kind of camera in a different way. In his picture you could see everything very clearly, even the smallest thing. This kind of photo was called a Daguerreotype.

Soon, other people began to use Daguerre's way. Travelers brought back wonderful photos from all around the world. People took pictures of famous buildings, cities and mountains.

In about 1840, photography was developed. Then photographers could take pictures of people and moving things. That was not simple. The photographers had to carry a lot of films and other machines. But this did not stop them, for example, some in the United States worked so hard.

Mathew Brady was a famous American photographer. He took many pictures of great people. The pictures were unusual because they were very lifelike.

Photography also became one kind of art by the end of the 19th century. Some photos were not just copies of the real world. They showed our feelings, like other kinds of art.

1.The first photo was a picture of Niepce's _______.

A. business B. house

C. garden D. window

2.The Daguerreotype was _______.

A. a Frenchman B. a kind of picture

C. a kind of camera D. a photographer

3.This passage tells us_______.

A. how photography was developed

B. how to show you ideas and feelings in pictures

C. how to take pictures in the world

D. how to use different cameras

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年內(nèi)蒙古包頭第九中學(xué)高二上期中英語試卷（解析版） 題型：閱讀理解

The small number of newborn babies, which has been caused by high prices and the changing social situation of women, is one of the most serious problems in Asia. When people talk about it, you can hear a word invented in Japan, “DINKS”, which means Double Income No Kids.

In many major Asian cities like Seoul, Singapore, and Tokyo, the cost of a house is extremely high. A young couple who want to buy their own house may have to pay about $3000,000 (though prices have fallen). For a flat with one bedroom, one dining-room, a kitchen, and a bathroom, the couple will pay about $900 a month. What’s more, if they want to have a child, the child’s education is very expensive. For example, most kindergarten charges are at least $5,000 a year. In such a situation, it’s difficult to afford children.

The number of married women who want to continue working increases rapidly because they enjoy their jobs. However, if they want to have children, they immediately have serious problems. Though most companies allow women to leave their jobs for a short time to have a baby, they expect women with babies to give up their jobs. In short, if they want to bring up children properly, both parents have to work, but it is hard for mothers to work. Indeed, women who want to continue working have to choose between having children or keeping their jobs.

In a word, Asian governments must take steps to improve the present situation as soon as possible.

1. What is the main problem being discussed in the passage?

A. The small number of newborn babies.

B. The changing social situation of women.

C. The high prices of houses and education.

D. The necessary steps of Asian government.

2.According to the passage, which of the following is true?

A. It is easy for a couple to afford a child in Asia.

B. The prices of houses in Asia are quite low now.

C. Fewer and fewer married women want to have a job.

D. The word “DINKS” appeared in an Asian country.

3.To buy a flat and send a child to kindergarten, how much will a couple pay each year?

A. $5,000. B. $5,900.

C. $10,800. D. $15,800.

4. The writer seems to believe that Asian governments should ________.

A. let women stay at home and have a baby

B. allow only one of the parents to go out to work

C. care for the growing needs of women for jobs

D. punish the companies that permit women to leave

查看答案和解析>>

科目：高中英語 來源：2016屆天津第一中學(xué)高三上學(xué)期第二次月考英語試卷（解析版） 題型：單項(xiàng)填空

Sometimes I act as a listening ear for fellow students ______ what is bothering them.

A. to talk over B. talked about

C. talk about D. having talked over

查看答案和解析>>

科目：高中英語 來源：2016屆陜西西安第一中學(xué)高三上學(xué)期期中英語試卷（解析版） 題型：閱讀理解

To prevent the deserts coming near, China has planted billions of trees---to replace destroyed forests and as barriers against the sand. This isn’t a cure, though, say experts, as thirsty trees can make the problem worse by taking in groundwater.

“Planting tress is one way, but it isn’t that simple. It doesn’t solve the basic issue of water resources,” says Wu Bo, a professor. “We need to calculate how much water the trees will absorb, or else it could have a negative effect.”

Villagers in Zhengxin have taken on this challenge, with limited success. When the irrigation channels began to run dry, Lu Xianglin switched from wheat to cotton on his land. He also planted trees to protect his fields from sandstorms. He says he still gets good yields（產(chǎn)量） using flood irrigation and earns a good income for his family.

Other farmers haven’t stuck it out（堅(jiān)持到底）: about one in three have left Zhengxin in the past 10 years after their wheat crops died. Young people who can find jobs in the towns rarely return.

Last week, Mr Lu joined the other men in his village on a government-arranged trip to see the land that has been set aside for their relocation, nearly 40 miles to the south. The next day, he was back, shaking his head at the plan. The idea of uprooting his family troubles him, as does the idea of giving up the land that fed his forefathers. He prefers to stay and keep up the fight.

“With enough water, this problem can be solved,” Lu says. “We can plant trees and grass, and they will grow bigger. That will stop the desert.”

Experts say that farmers could switch to drip irrigation （滴灌）to lessen their water intake for growing crops. Elsewhere in the region, farmers have built brick greenhouses as part of a plan to grow vegetables using less water. Roadside signs urge farmers to “Save Water, Protect the Environment”.

1. The negative effect of planting trees in deserts is that __________.

A. it can make groundwater become less

B. it can prevent the sand moving freely

C. it can stop crops growing well

D. it can get the soil to become poor

2.Why did Mr. Lu NOT accept the idea of relocation?

A. Because the plan of relocation will cost him much money.

B. Because his family had trouble moving away.

C. Because he was reluctant to give up his land.

D. Because he would rather stay than fight against the deserts.

3.What can we infer from the passage?

A. The deserts drive more and more people to leave their homes for their lives.

B. People have no means to fight against the land becoming desert.

C. Water is the biggest barrier for people to stop the desert.

D. Planting trees cannot solve the problem of desertification of farmland.

4.What advice is given by experts to save water?

A. To plant more trees.

B. To build greenhouses.

C. To change crops.

D. To use drip irrigation.

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年江蘇淮陰中學(xué)高二上第二次月考英語試卷（解析版） 題型：單項(xiàng)填空

He would be in a better university now________ to too many computer games when young.

A. were he not addicted B. if he was not addicted

C. had he not addicted himself D. had he not been addicted himself

查看答案和解析>>

科目：高中英語 來源：2016屆吉林實(shí)驗(yàn)中學(xué)高三上學(xué)期第五次模擬英語試卷（解析版） 題型：書面表達(dá)

假設(shè)你是高三學(xué)生劉珊，你校正在組織美國哥倫比亞大學(xué)（Columbia University）招生活動，請你根據(jù)以下要點(diǎn)提示給你在美國的筆友Russ寫一封信。

要點(diǎn)：

1. 通過校內(nèi)選拔考試 （selective test） 的同學(xué)將參加該著名大學(xué)于一月份組織的英語筆試、口試和面試；

2. 你本人對此很感興趣，正在積極備考；

3. 希望Russ給出一些有關(guān)英語學(xué)習(xí)的建議。

注意： 1．詞數(shù)：100左右；

2．可適當(dāng)增加細(xì)節(jié)，以使行文連貫；

3．開頭與結(jié)尾已為你寫好,請不要重新抄寫。

Dear Russ,

How is everything going?

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

Yours,

Liu Shan

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年湖南岳陽一中高一上學(xué)期期中英語試卷（解析版） 題型：完形填空

完形填空

閱讀下面短文，從短文后各題所給的A,B,C,D四個選項(xiàng)中選出最佳選項(xiàng)

Editors of newspapers and magazines often go too far in supplying readers with facts. Last year a reporter by a well-known magazine wrote an article on the president’s in a new African republic. When the article arrived, the editor read the first sentence and then refused to it. The article began like this, “Hundreds of steps lead to the high surrounding the president’s palace.” The editor sent the reporter a telegram directing him to find out the number of steps and height of the wall.

The reporter set out to get these important facts at once, but it him a long time to send them back. Meanwhile, the editor was growing , for the magazine would soon be . He sent the reporter two urgent(加急的) telegrams, but received reply. He sent another, yet the reporter again to reply. The editor unwillingly published the article it had been written. A week later, the editor at last the reporter, who told him in the letter that not only had he been arrested(逮捕)but he had been sent to . The poor man had been seized by the police while the 1804 steps leading to the 15-foot wall around the palace.

1.A. answered B. sent C. wanted D. taken

2.A. hometown B. office C. palace D. family

3.A. publish B. rewrite C. sign D. talk about

4.A. palace B. wall C. country D. prison

5.A. quickly B. later C. hurriedly D. immediately

6.A. exact B. large C. small D. unknown

7.A. took B. spent C. got D. found

8.A. glad B. fast C. anxious D. happy

9.A. sold B. sent C. shown D. printed

10.A. no B. much C. one D. any

11.A. managed B. failed C. had D. ought

12.A. until B. like C. when D. as

13.A. met with B. looked for C. came across D. heard from

14.A. a hotel B. prison C. the palace D. the office

15.A. counting B. going C. measuring D. drawing

查看答案和解析>>

同步練習(xí)冊答案