Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing or whistle when you are happy.

Some scientists believe that birds do sing some of the time just because they are happy. However they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.

Do you know what a ‘territory’ is? A territory is an area that an animal, usually the male, claims as its own. Only he and his family are welcome there. No other families of the same species are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and threaten you, you might shout. Probably this would be enough to frighten him away.

If so, you have actually scared the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting（筑巢）season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.

Birds sing loudest in the spring when they are trying to attract a mate and warn others not to enter the territory of theirs.

You can see that birds have a language of their own. Most of it has to do with attracting mates and setting up territories.

1.Some scientists believe that most of the time bird’s singing is actually________.

A. an expression of happinessB. a way of warning

C. an expression of angerD. a way of greeting

2.What does the underlined word “territory’’ mean?

A. A place where families of other species are not accepted

B. A place where a bird may shout at the top of its voice

C. An area for which birds fight against each other

D. An area which a bird considers to be its own

3.Why do birds keep on singing at nesting season?

A. Because they want to invite more friends

B. Because their singing helps frighten outsiders away

C. Because they want to find outsiders around

D. Because their singing helps get rid of their fears

4.How does the writer explain bird’s singing?

A. By comparing birds with human beings

B. By reporting experiment results

C. By describing birds’ daily life

D. By telling a bird’s story

We each have a unique genetic(基因的, 遺傳的)make-up. Every cell of our 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 our skin to the way our brain works. We have one of several billion combinations of DNA which come from the random mixing of our parents’ genes. Except for identical twins(同卵雙胞胎), no one has the same combination as another person. We are unique! We are unique in another way, too: in the way we are raised and all the experiences we have from before birth to adult life. These experiences influence us, our behaviour and attitudes, and the choices we make.

But are genes or life experiences more important in shaping our 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(繼承). 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 behavior. 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. Both our genes and our experiences make us who we are.

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

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

D. We cannot easily change our physical appearance.

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

A. Our love of sports. B. Our attitude to risk-taking.

C. Our skill at bungee jumping. D. Our ability to take drugs.

閱讀下面短文, 根據(jù)以下提示: 1)漢語提示, 2)首字母提示, 3)語境提示, 在每個空格內(nèi)填入一個適當(dāng)?shù)挠⒄Z單詞, 并將該詞完整地寫在右邊相對應(yīng)的橫線上。所填單詞要求意義準(zhǔn)確, 拼寫正確。

Last Saturday evening I arrived at the concert hall very early. The performance began at 7: 30. All the1.(座位)were not free. We were so excited by the special sound of heavy metal2.we couldn’t h3.crying and jumping. Suddenly I heard the sharp sound of an ambulance and saw a young man t4.out of the hall quickly. 5. must have been injured in the excitement, but this didn’t stop the concert. It still went on smoothly. When the concert was6., the singer thanked us7.our enthusiasm. We kept cheering for some time. To tell the t8., I’m really crazy about the singing with heavy metal. I am sure I’ll be a fan of this type of popular9.(音樂). And I think more and more people will become10.(感興趣的)in it very soon.

隨著網(wǎng)絡(luò)的普及，越來越多的中學(xué)生甚至小學(xué)生都注冊了個人博客，對此有人贊同，也有人反對。請根據(jù)下表中的提示寫一篇英語短文，談?wù)勅藗儗Υ爽F(xiàn)象的看法并發(fā)表自己的觀點(diǎn)。

注意：1、詞數(shù)120左右。 2、可適當(dāng)增加細(xì)節(jié)，以使行文連貫。

參考詞匯：博客—blog

With the popularity of the Internet, a growing number of middle school students start their own blogs on the Internet,

As city boy accustomed to the concrete building, streams of vehicles and skies of smog, I found farm life “eye-opening” experience.

A. the; a B. the; an

C. a; the D. a; an

downloading of large numbers of apps is one of the most risky behaviors someone with a smartphone can engage in.

A. Cautious B. Public C. Random D. General

The report has found that more and more Chinese have an American or British temporary visa for holiday spending in recent years.

A. stood for B. applied for

C. accounted for D. searched for

The rising frequency for smoggy days puts me into deep that maybe one day citizens will have to rely on masks to survive.

A. doubt B. worry C. shock D. faith

While watching television, .

A. the doorbell rang B. the doorbell rings

C. we heard the doorbell ring D. we heard the doorbell rings

Emergencies and unexpected situations happen all the time.

A. may B. can C. must D. should