Do you want to know how and why a fall leaf changes color? We first have to understand what leaves are and what they do.

Leaves are the world’s food factories. Plants take water from the ground through their roots and take CO2 from the air. Plants use sunlight to turn water and CO2 into glucose(葡萄糖), a kind of sugar. Plants use it as food for energy and growing.

A chemical called “chlorophyll” in the leaves gives plants their green colour. As summer ends and autumn comes, the days get shorter and shorter, and trees “know” to begin getting ready for winter.

During winter, there is not enough sunlight or water. Trees rest during this time and live on the food they store during the summer. They begin to shut down their food-making factories. As the green chlorophyll disappears from the leaves, we begin to see yellow and orange leaves.

The bright reds and purples we see in leaves are made mostly in autumn. In some trees, like maples, sunlight and the cool nights of autumn turn the glucose in the leaves into a red colour. And we can enjoy the beautiful red leaves during autumn.

1.Which should be in the box? sunlight+ +CO2 glucose

A. air B. sugar C. water D. wind

2.The underlined word “chlorophyll” means __________.

A.叶绿素 B. 脂肪 C.蛋白质 D.淀粉

3.The leaves turn yellow because they are short of(缺少) __________.

A. water and CO2

B. glucose and energy

C. sunlight and water

D. sunlight and CO2

4.Which of the following is NOT true?

A. When autumn comes, the days get shorter and shorter.

B. During winter trees live on the food they store in summer.

C. During winter some of yellow and orange colors are still in the leaves.

D. Trees begin to stop making food in summer.

5.This passage tells us_____________.

A. the plants can grow well only with the sunlight

B. there are all kinds of plants on the earth

C. not all the colors of the leaves are from chlorophyll

D. maple leaves change the color as other trees

It is Mother's Day. John is busy with his work during the day. When he passes by a flower shop in the evening, he thinks, ‘I'll send Mum some roses (玫瑰).’ While John is looking at the flowers, a young man comes inside. ‘How many roses can I buy for only five dollars , madam?’ he asks. The shopkeeper tells him that a dozen of roses(一打玫瑰) is forty dollars. Maybe he can buy some carnations (康乃馨). They are much cheaper.

‘No, I only want to have red roses,’ he says. ‘My mum was badly ill and I didn't spend much time with her. Now I want to give her something special, it must be roses because rose is her favorite.’

After hearing it, John says he can help him pay for the rest (其余) of the money. The shopkeeper is moved (感动的) and says, ‘Well, lovely young men, thirty dollars a dozen, only for you.’ Taking the roses, the young man almost jumps into the air and runs out of the shop. Then John pays for his dozen of roses and tells the shopkeeper to send them to his mother.

As he walks out, he feels nice. Suddenly he sees the young man crossing the street and going into a park. But soon John knows it is not a park but a cemetery (墓地). Crying, the young man carefully puts down the roses, ‘Mum, oh, Mum, why didn't I tell you how much I loved you? God, please help me find my mum and tell her I love her.’

Seeing this, John turns and quickly walks to the shop. He will take the flowers home himself.

1.The shopkeeper asks the young man to buy carnations because ________.

A.carnations are nicer than roses

B.John buys all the roses.

C.roses are cheaper than carnations

D.carnations are cheaper than roses

2.The young man is crying at the cemetery because he ________.

A.can’t tell his mother he loved her himself

B. spends all his money on the roses

C.feels sorry to ask John to pay for his flowers

D.has no money for his sick mother

3.Finally John takes the flowers home himself because he wants to ________.

A.tell his mother he loved her himself

B.ask his mother for more money

C.tell his mother the young man's story

D.ask his mother if she likes roses

4.What is the main idea of the article?

A.Buy roses for mother when she is ill.

B.Let mother know how much you love her.

C.Work hard to make money for mother.

D.Send mother flowers on Mother's Day.

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