We each have a unique genetic (基因的，遺傳的) make-up. Every cell of your body has the same set of about 100,000 separate genes made of DNA. These are the instructions for producing a person. Genes decide everything from the colour of your skin to the way your brain works. You have one of several billion binations of DNA which e from the random(隨機(jī)的，任意的) mixing of your parents’ genes. Except for identical twins (同卵雙胞胎), no one has the same bination as another person. You are unique! You are unique in another way too: in the way you are raised and all the experiences you have from before birth to adult life. These experiences influence you, your behaviour and attitudes, and the choices you make.

But are genes or life experiences more important in shaping your appearance and personality? Scientists are studying twins to find out. One set of twins occurs every 70 births---some are identical and others are non-identical twins. Identical twins are special because they share exactly the same genes and often the same environment. Non-identical twins are more like ordinary brothers and sisters.

Some identical twins have been adopted and brought up in different homes. With identical genes but a different home environment, scientists can study twins to see how much a particular feature depends on the genes we inherit. For example, we know that eye problems, like short-sightedness, are mostly genetic. But resistance to pain is largely dependent on experiences. Genes also influence our eating habits. Identical twins brought up apart often like to eat at the same time of day and feel full after eating the same amount. Non-identical twins in similar circumstances have more varied eating habits. Identical twins are also more likely to follow the same patterns for marriage and divorce than non-identical twins.

Scientists are trying to identify the different genes that influence our behaviour. Some people are thrill-seekers and get into risk-taking and adventurous activities. They take up extreme sports like bungee jumping and possibly take drugs. Scientists have discovered a gene which affects this.

We could ask, “Are our lives determined by our genes or our upbringing?” Scientists are learning more all the time, but it is certainly true that both are important in making us who we are.

1.What is the main idea of the first paragraph?

A. We cannot easily change our physical appearance.

B. How we turn out depends on our parents’ genes.

C. Everyone has a physical double somewhere in the world.

D. Both our genes and our experiences make us who we are.

2.Why are scientists studying twins?

A. To find out how many twins are born every year.

B. To discover what shapes us as individuals.

C. To pare differences between twins.

D. To study brother-and-sister relationships.

3.According to the passage, __________.

A. one in 70 twins are genetically identical

B. non-identical twins are usually not of the same sex

C. twins separated at birth behave exactly the same

D. identical twins are genetically the same

4.Which of the following is most affected by experience according the passage?

A. Eating habits. B. Eye-sight.

C. Pain resistance. D. Marriage patterns.

5.What does the underlined “this” in Paragraph 4 refer to?

A. Our love of sport.

B. Our attitude to risk-taking.

C. Our skill at bungee jumping.

D. Our ability to take drugs.

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科目：高中英語 來源：2014-2015學(xué)年遼寧師大附中高三上學(xué)期10月模塊考試英語試卷（解析版） 題型：完形填空

第二部分 完形填空(共20小題;每小題1.5分，滿分30分)

閱讀下面短文，從短文后各題所給的四個(gè)選項(xiàng)(A、B, C和D)中，選出可以填入空白處的最佳選項(xiàng)，并在答題卡上將該項(xiàng)涂黑。

When I was 8, a gentleman came to my orphanage（孤兒院）and taught us how to do woodworking projects.

I remember my first project—a small table. I was so ____ of it that I looked upon it as if I had created a(an) _____ . It was absolutely beautiful and it had taken me six weeks to ______it. I could hardly wait to give it to Mother Winters as a _____. She was the head mistress of our orphanage, who was always _____ with us.

As the tables were not dry from the clear coating, the man told us to wait a few days before taking them to our dormitories. But I was just so ____and happy that I couldn’t wait. I dashed out like a ______ , carrying my table, smiling from ear to ear.

When I reached the dormitory I placed the little table beside my bed. I was _____it when Mother Winters entered. She walked over to the table. Running her hand _____ it, she noticed that it was still wet.

“Were you ______to bring this home?” she asked.

“No, ma’am,” I _____ with my head down.

She ordered me to throw the table out and so I did. After she left, I immediately opened the door to get it back. There was _____stuck all over. I brushed and cried, but it would not come off.

I hid the table in my closet and never _____it. A year later while cleaning up, I gave the table to Mother Henderson, my houseparent（宿管員）, thinking that she would _____it away.

Thirty years later at a reunion, I ____that Mother Henderson was living nearby, so I drove up to see her. We talked cheerfully for long. As I was about to leave, she asked me to come down to her_____ to get something important. I followed her _____ into a dark corner. She picked something up. _____she turned around, I could see that she was holding a little table.

Mother Henderson kept the little table that I had given up for lost so long ago.

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Every time you go to the supermarket you come away with your purchases packed in plastic bags. But wouldn’t it be kinder to the environment if you asked for paper bags instead?

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But paper bags do break down more quickly than plastic bags. They don’t endanger wildlife, either.

So what should we do? One possible solution would be to use biodegradable plastic bags. “Biodegradable” means that the bags break down naturally just like a piece of banana peel when it is left outside.

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Either the judge or the lawyers ______ wrong on the case at that moment.

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Our government’s plan to fight against air pollution will focus on _____ information and handling PM2.5.

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When I met him the other day，it was the first time we ______ each other since we graduated from school.

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______ is generally accepted, economic growth is determined by the smooth development of production.

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The good thing about children is that they _______ very easily to new environments.

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第二節(jié)（共10小題；每小題1.5分，滿分15分）

閱讀下面材料，在空白處填入適當(dāng)?shù)膬?nèi)容（不多于3個(gè)單詞）或括號(hào)內(nèi)單詞的正確形式。

Snake dishes have become popular1. recent years. Snake meat in various flavors (風(fēng)味) is often seen in restaurant ads. Eating snake seems to be now in vogue(盛行), and if you haven’t eaten snake yet, you 2.(consider) “out of date”. But I wonder3. all the trends are worth following.

Some people may defend themselves _4. saying that snake meat is nutritious. But these people don’t realize that many parasites(寄生蟲)，5. do harm to our health, are found inside snakes.

According 6. a survey, about 1000 tons of snakes are eaten every year in China and sometimes as 7. as 10 tons of snakes are served on dinner tables in Shenzhen in a single day!

These figures warns us that if no action is taken, 8. number of snakes will drop and make an increase in mice and worms population, which will 9.in a decrease(減產(chǎn)) of crop output. Who will see such tragedy happen?

So let’s start not to eat snakes any more because “to protect the snake is to protect 10.”

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