阅读下列短文,从每题所给的A、B、C、D四个选项中,选出最佳选项。

Once there was a baby eagle living in a nest (巢) on a cliff (山崖).The baby eagle loved his nest.It was warm, soft and comfortable.And even better, he had all the food and love that his mother could give.Whenever the baby eagle was hungry, his mother would always come just in time with the delicious food he liked.

He was growing happily day after day.But suddenly his world eagle changed.His mother stopped coming to the nest, he was full of sadness and fear.He thought he would die soon.He cried, but nobody heard him.

Two days later mother appeared with some nice food.The baby eagle was wild with joy.But his mother put the food at the top of the mountain and then looked down at her baby.

The baby eagle cried out, “Mum, why did you do this to me? I’m hungry.Don’t you know I will die if I have nothing to eat?”

“Here is the Last meal I give you.Come and get it by yourself.” his mother said.Then she flew down and pushed the baby eagle out of the nest.

The baby eagle fell down, faster and faster.He looked up at his mum.“ Why do you abandon me?” He looked down at the earth.The ground was much closer.Then something strange happened.The air caught behind his arms and he began to fly! He wasn’t moving to the ground any more.Instead, his eyes were pointed up at the sun.

You are flying! You can make it!” His mother smiled.

1.Which of the following is TRIJE about the baby eagle’s life before his mother stopped coming to the nest?

A.lie lived in a nest in the tree.

B.He was always cold and hungry.

C.He lived very happily with friends.

D.His mother offered him nice food.

2.How did the baby eagle feel as soon as lie saw his mother coming again?

A.Sad

B.Afraid

C.Happy

D.Angry

3.What does the word “abandon” mean?

A.保护

B.抛弃

C.歧视

D.拯救

4.We can infer (推断) from the story that _____________

A.The baby eagle lost his mother

B.The baby eagle fell down and died

C.The baby eagle was still angry with his mother.

D.The baby eagle could get food himself.

It’s never a real problem for us when the weather gets cold. We can put on more clothes, stay next to a fireplace, turn on the air conditioner or simply travel to a warmer city to spend the winter – people have many different ways of dealing with the cold.

But things are not as easy for plants. Unlike humans, plants can’t move to escape the cold or generate heat ( 发热) to keep themselves warm. So how do they manage to survive the freezing winter?

It turns out that plants have their own strategies (策略) too, said a study published on Dec 22 in the journal Nature.

According to researcher Amy Zanne of George Washington University, US, the cold is a big challenge for plants. Their living tissues (活组织) can be damaged when they freeze. “It’s like a plant’s equivalent to frostbite ( 相当于冻疮),” Zanne told Science Daily. Also, the process of freezing and thawing (解冻) can cause air bubbles (气泡) to form in the plant’s water transport system. “If enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant,” she explained.

To live through cold weather, plants have developed three traits (特性) , according to the study. Some plants, such as oak trees(橡树), avoid freezing damage by dropping their leaves before the winter chill sets in – effectively shutting off the flow of water between roots and leaves – and growing new leaves and water transport cells when the warm spring returns.

Other plants, pine trees(松树) for example, protect themselves by narrowing their water transport cells, which makes it easier for cells to travel among air bubbles.

The third strategy is also the most extreme – some plants die on the ground in winter and start growing as new plants from seeds when conditions get warmer.

However, the study also found that these smart strategies were developed very slowly – over millions

of years of evolution ( 进化). This leads scientists to worry that plants may not be able to deal with human-caused climate change, which has only started occurring over the past few decades.

Scientists are hoping that this study can help people find possible ways to save plants from the threat

of climate change.

1.What is the article mainly about?

A. Why plants are not afraid of the winter chill.

B. The ways that plants survive cold weather.

C. Changes in plants’ water transport system in winter.

D. How plants evolve to keep up with climate change.

2.According to the article, if a plant freezes in the winter, ______.

A. it produces more living tissues to stay alive

B. its leaves quickly fall out and its roots begin to die

C. lots of air bubbles form in its water transport system

D. its water transport system could be blocked in the spring

3.What are scientists worried about when it comes to plants according to the article?

A. Plants may not be able to adapt to the increasingly cold climate.

B. Human activities might have a great impact on the pace of plants’ evolution.

C. Plants may not be able to evolve fast enough to adapt to human-caused climate change.

D. The strategies plants develop are not good enough to protect them against cold.

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