In the late 1950s, a Russian geneticist called Dmitry K. Belyaev attempted to create a tame (馴化的) fox population. Through the work of a breeding programme at the Institute of Cytology and Genetics at Novosibirsk, in Russia, he sought to find the evolutionary pathway of tame animals. His test subjects were silver-black foxes, a melanistic (帶黑色的) version of the red fox that had been bred in farms for the color of their fur.
He selected the animals based on how they responded when their cage was opened. About 10% of the foxes displayed a weak “wild-response”, meaning they were docile around humans. Those that hid in the corner or made aggressive voices were left in the farm. Of those friendly foxes, 100 females and 30 males were chosen as the first generations of parents.
When the young foxes were born, the researchers hand-fed them. They also attempted to touch or pet the foxes when they were two to two-and-a-half months old, for strictly measured periods at a time. If the young foxes continued to show aggressive response, even after significant human contact, they were thrown away from the population—meaning they were made into fur coats. In each selection, less than 10% of tame individuals were used as parents of the next generation.
By the fourth generation, the scientists started to see dramatic changes. The young foxes were beginning to behave more like dogs. They wagged their tails and “eagerly” sought contact with humans. By 2005-2006, almost all the foxes were playful, friendly and behaving like domestic dogs. The foxes could “read” human hints and respond correctly to gestures or glances.
1.What do we know about Belyaev’s breeding plan?
A. It explains how red foxes were bred.
B. It focuses on how tame animals evolved.
C. It explains why pet foxes became popular.
D. It concentrates on why tame animals disappeared.
2.How did he choose his test foxes in the experiment?
A. By appearance.
B. By color.
C. By reaction.
D. By flexibility.
3.What can be inferred from Paragraph 3?
A. Smart foxes were used for testing.
B. The purpose of selection was unclear.
C. Friendly foxes were kept on testing.
D. The selection was not exact and thorough.
4.What is the distinguishing characteristic of the fourth generation foxes?
A. Behaving in a friendlier way.
B. Eating plants.
C. Having drooping ears.
D. Having shortened legs.
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科目:高中英語 來源:貴州省2017屆高三第十一次模擬(5月)英語試卷 題型:閱讀理解
A Guide to the University
Food
The TWU Cafeteria is open 7 a.m. to 8 p.m. It serves snacks, drinks, ice cream bars and meals. You can pay with cash or your ID cards. You can add meal money to your ID cards at the Front Desk. Even if you do not buy your food in the cafeteria, you can use the tables to eat your lunch, to have meetings and to study.
If you are on campus in the evening or late at night, you can buy snacks, fast food, and drinks in the Lower Café located in the bottom level of the Gouglas Centre. This area is often used for entertainment such as concerts, games or TV watching.
Relaxation
The Globe, located in the bottom level of McMillan Hall, is available for relaxing, studying, cooking and eating. Monthly activities are held here for all international students. Hours are 10 a.m. to 10 p.m, closed on Sundays.
Health
Located on the top floor of Douglas Hall, the Wellness Centre is committed to physical, emotional and social health. A doctor and nurse is available if you have health questions or need immediate medical help or personal advice. The cost of this is included in your medical insurance. Hours are Monday to Friday, 9 a.m. to noon and 1:00 to 4:30 p.m.
Academic Support
All students have access to the Writing Centre on the upper floor of Douglas Hall. Here, qualified volunteers will work with you on written work, grammar, vocabulary, and other academic skills. You can sign up for an appointment on the sign-up sheet outside the door, two 30-minute appointments per week maximum. This service is free.
Transportation
The TWU Express is a shuttle service. The shuttle transports students between campus and the shopping center, leaving from the Mattson Centre. Operation hours are between 8 a.m. and 3 p.m. Saturdays only. Round trip fare is $1.
1.What can you do in the TWU Cafeteria?
A. Have meals and meet with friends.
B. Buy drinks and enjoy concerts.
C. Do homework and watch TV.
D. Add money to your ID and play chess.
2.Where and when can you cook your own food?
A. The Lower Café, Sunday. B. The Globe, Friday.
C. The TWU Cafeteria, Friday. D. The McMillan Hall, Sunday.
3.How can you seek help from the Writing Centre?
A. By applying online. B. By calling the center.
C. By going to the center directly. D. By filling in a sign-up form.
4.What is the function of TWU Express?
A. To carry students to the lecture halls.
B. To transport students to and from the stores.
C. To take students to the Mattson Centre.
D. To provide students with campus tours
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科目:高中英語 來源:安徽省滁州市2016-2017學(xué)年高二5月聯(lián)考英語試卷 題型:七選五
If you find that your teacher is unfair to you,think about what is happening.Try to find out whether your teacher really dislikes you,or whether something else is going on.Here are some questions to ask yourself:
1.Ask your classmates if they are having trouble with the teacher,too.If they say yes,perhaps your teacher is to blame.
Are you working up to your ability?Maybe you got a C in your last test,and your teacher told you that you could do better.2.But the teacher didn't say anything to him!Isn't this unfair?Well,it could be that your teacher knows that you could do better if you put more effort into it.3.
Are you more sensitive than other students?4.However,if you react to criticism quite differently from others, this could be a reason why you think your teacher doesn't like you.
Does your teacher seem to act unfairly all the time,or just once in a while?Think about the harsh(苛刻的)things your teacher has done to you.5.If your teacher really hates you,you would probably be picked on all the time.If your teacher has acted unfairly only a few times,then there's probably something else going on.
A.Are you interested in your lessons?
B.And the kid sitting beside you got a C,too.
C.There's nothing wrong with being sensitive.
D.Are you getting along well with your classmates?
E.Teachers often grade students by different standards.
F.Are you the only person being treated badly?What about others?
G.Are these things happening every day,or just once or twice a month?
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科目:高中英語 來源:甘肅省2017屆高三下學(xué)期第四次校內(nèi)診斷考試英語試卷 題型:完形填空
Although I love my life,it hasn't been a lot of fun as I've been ill for 28 years.
Music has always been a great love of mine and,in my 20s,when my____was more manageable,I____ten years as a professional singer in restaurants,playing and singing folk songs.____that was years ago and times have changed.____I live with my mother on a country farm.
Two years ago,I decided that I would need to have some kind of extra work to____my disability pension(殘疾撫恤金).____I needed to sleep in the afternoons,I was limited in my____.I decided that I would consider____to singing in restaurants.
My family are all musicians,so I was____when I went into our local music store.I explained that I wanted to sing again but using recorded karaoke music.I knew that discs were very expensive and I really didn't have a lot of ____to get started.And____you find only three to four songs out often on a disc that you can____use.
When I told the owner of the shop about my____,he gave me a long thoughtful____."This means a lot to you, doesn't it?"he said."Come with me."
He led me____the crowded shop and to a bench with a large professional karaoke box on it.He placed his large hand____on his treasure and said,"I have 800 karaoke songs in here.You can take your____and I'll record them for you.That should get you started."
I____.Thanking him,I made a time with him to listen to all the songs and choose____that I could sing.I have come full circle with his help.
His____still warms my heart and makes me do just that bit extra,when I have the chance.
1.A. loneliness B. sadness C. sickness D. tiredness
2.A. set B. shared C. kept D. enjoyed
3.A. Gladly B. Eventually C. Surprisingly D. Unfortunately
4.A. Then B. Now C. Sometime D. Meanwhile
5.A. add up to B. get rid of C. make up for D. take advantage of
6.A. As B. If C. Though D. Before
7.A. movement B. condition C. positions D. choices
8.A. reaching out B. living up C. going back D. getting on
9.A. invited B. interviewed C. found D. recognized
10.A. energy B. time C. money D. knowledge
11.A. thus B. once C. often D. seldom
12.A. hardly B. actually C. nearly D. formerly
13.A. job B. family C. offer D. idea
14.A. face B. look C. view D. sight
15.A. over B. along C. through D. towards
16.A. unhappily B. pitifully C. lovingly D. gratefully
17.A. tum B. pick C. role D. step
18.A. had to cry B. ought to cry C. could have cried D. should have cried
19.A. more B. the rest C. few D. the ones
20.A. courage B. devotion C. trust D. kindness
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科目:高中英語 來源:吉林省2017屆高三下學(xué)期第八次模擬考試(期中)英語試卷 題型:短文改錯(cuò)
假定英語課上老師要求同桌之間交換修改作文,請(qǐng)你修改你同桌寫的以下作文。文中共有10處語言錯(cuò)誤,每句中最多有兩處。每處錯(cuò)誤僅涉及一個(gè)單詞的增加、刪除或修改。
增加:在缺詞處加一個(gè)漏字符號(hào)(∧),并在其下面寫出該加的詞。
刪除:把多余的詞用斜線(\)劃掉。
修改:在錯(cuò)的詞下劃一橫線,并在該詞下面寫出修改后的詞。
注意:1.每處錯(cuò)誤及其修改均限一詞;
2.只允許修改10處,多者(從第11處起)不計(jì)分。
Today we had the honor of invite Professor Hudson, a foreign teacher from Beijing University, to give us an English lesson. All of us were deeply impressing by this unforgettable English lesson. The professor began the class with an amusing English story, that attracted our attention at once. He spoke slowly and clearly so that we could follow her well. Great inspired, most of us took an active part in classroom activities. After class, many students being interviewed spoke highly of him. They said that never they experienced such interesting a class. From his lesson, we came to a conclusion what it is not so difficult to learn English but we find a good way.
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科目:高中英語 來源:湖南省衡陽市2017屆高三第二次模擬(實(shí)驗(yàn)班)英語試卷 題型:短文填空
I remember the occasion when mother sent me to the main road, about twenty yards away from our house, to invite a passing group of seasonal work-seekers for a meal. She1.(instruct) me to take a basket along and collect dry cow dung(牛糞) for making a fire. I was then to prepare the meal for the group of work-seekers.
2. thought of making an open fire outside at midday,and3.(cook)in a large three-legged pot in that intense heat, was sufficient to upset even an angel. I did not manage to hide my feelings from my mother and, after serving the group, she called me to the veranda(走廊)4. she usually sat to attend to her sewing and knitting.
5. straight into my eyes, she asked “Why did you get angry6. I requested you to prepare a meal for those poor people?”7. my attempt to deny her blame,using the heat of the fire and the sun as an excuse for my rude behavior, mother, she gave me a firm look,8.(say), “You cannot detect what trouble may lie ahead of you.”
I9. (sudden) realized that if I had refused to offer this group of people a meal,10. would be impossible that in my travels some time in the future,I would get these individuals' help.
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科目:高中英語 來源:河北省2016-2017學(xué)年高一下學(xué)期5.21周練英語試卷 題型:七選五
Red envelopes have been related to the Chinese Lunar New Year for long. I myself have had plenty of experiences both receiving and giving out red envelopes in the past, 1. I mean, who doesn’t love free money?
I’m truly surprised by the extent of people’s obsession with virtual red envelopes this year. In fact, everyone I know spent at least a day or two crazily shaking their smart phones, 2. Thanks to messaging app giant We Chat’s new feature which allows users to send money electronically, grabbing virtual red envelopes has never seemed so easy.
3. here’s how it works. Givers link their We Chat to their bank accounts, and then they can send specified amounts of money to their We Chat accounts through a personal message. They can also put the cash up for grabs in chat groups full of friends, and anyone who acts fast enough will get a share. 4.
In theory, this sounds like a fun game. I’m always for some harmless fun in life, so my natural response would be: Why not? Moreover, I’ve always believed that it’s human nature to want free stuff, regardless of whether you actually need it or not. This may not be a good quality, but it’s not against the law, 5. Considering these reasons, I really can’t fault anyone for their enthusiasm in grabbing virtual red envelopes. I would have done it too, had I not thought linking We Chat to my bank accounts was too much trouble.
A. and we know everyone likes money.
B. and generally speaking, it’s been fun.
C. if you want to be good at grabbing a red envelope.
D. Just in case you are one of the very few people still not on the bandwagon,
E. mostly trying to get as much lucky money as possible.
F. so I won’t get all judgmental here.
G. Later,receivers can transfer the funds from their We Chat back into their own bank accounts.
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科目:高中英語 來源:河北省2017屆高三下學(xué)期英語周練(5.15)試卷 題型:短文改錯(cuò)
假定英語課上老師要求同桌之間交換修改作文,請(qǐng)你修改你同桌寫的以下作文。文中共有10處語言錯(cuò)誤,每句中最多有兩處。每處錯(cuò)誤僅涉及一個(gè)單詞的增加、刪除或修改。
增加:在缺詞處加一個(gè)漏字符號(hào)(?),并在其下面寫出該加的詞。
刪除:把多余的詞用斜線(\)劃掉。
修改:在錯(cuò)的詞下劃一橫線,并在該詞下面寫出修改后的詞。
注意:1.每處錯(cuò)誤及其修改均僅限一詞;
2.只允許修改10處,多者(從第11處起)不計(jì)分。
The time we have is usual limited. However, even an hour is of much valuable. We should make full use of your time to do useful things. As students, we mustn’t study hard so as to serve for our society and our nation in the future. But it is pity that there are a lot of people who didn’t know the importance of time. They spend their valuable time smoke and drinking. They don’t realize that wasting time is the same as wasting a part of their life. Remember, don’t put off which you can do today until tomorrow.
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科目:高中英語 來源:遼寧省莊河市2016-2017學(xué)年高一下學(xué)期期中考試英語試卷 題型:短文改錯(cuò)
短文中有10處錯(cuò)誤,錯(cuò)誤涉及一個(gè)單詞的增加、刪除或修改。
增加:在缺詞處加一個(gè)漏字符號(hào)(∧),并在此符號(hào)下面寫出該加的詞。
刪除:把多余的詞用斜線(\)劃掉。
修改:在錯(cuò)的詞下劃一橫線,并在該詞下面寫出修改后的詞。
注意:1.每處錯(cuò)誤及其修改均僅限一詞;
2.只允許修改10處,多者(從第11處起)不計(jì)分。
Mao Zedong once wrote a poem in which he dreams of "walls of stone of hold clouds and rains tills a smooth lake rises in the narrow gorges".Now his dreams have been come true.The power of the Yangtze River has been harnessed by the Three Gorges Dam.Most of China's energy is produced by burning coal,that causes serious air pollution and increases global warming.Therefore,the dam will generate electricity equals to about 40 millions tons of coal without causing so many pollution.The reservoir has flooded a lot of cities and towns.More than a million of people has moved form their homes.About 800 historical relics have been submerged.
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