An absolute description of the threat hanging over the world's mammals,reptiles,amphibians and other life forms has been published by the well-known scientific journal,Nature.A special analysis carried out by the journal indicates that an astonishing 41% of all amphibians on the planet now face extinction while 26% of mammal species and 13% of birds are similarly threatened.

Many species are already critically endangered and close to extinction,including the Sumatran elephant,Amur leopard and mountain gorilla.But also in danger of vanishing（消失）for the wild,it now appears,are animals that are currently rated as merely being endangered.

In each case,the finger of blame points directly at human activities.The continuing spread of agriculture is destroying millions of hectares of wild habitats every year,leaving animals without homes,while the introduction of newly-come species,often helped by humans,is also damaging native populations.At the same time,pollution and overfishing are destroying ocean ecosystems.

"Habitat destruction,pollution or overfishing either kill off wild creatures and plants or leaves them badly weakened," said Derek Tittensor,an ocean ecologist at the World Conservation Monitoring Centre in Cambridge. "The trouble is that in coming decades,the additional threat of worsening climate change will become more and more common and could then kill off these survivors."

The problem,according to Nature,is worsened because of the huge gaps in scientists knowledge about the planet's biodiversity.Evaluations of the total number of species of animals and plants alive vary from 2 million to 50 million.In addition,evaluations of current rates of species' disappearances vary from 500 to 36,000 a year. "That is the real problem we face," added Tittensor. "The scale of uncertainty is huge."

In the end,however,the data indicate that the world is heading cruelly towards a mass extinction-which is defined as one involving a loss of 75% of species or more.This could arrive in less than a hundred years or could take a thousand,depending on extinction rates.

1.What's the main idea of the first two paragraphs?

A. Figures about some wild animals are astonishing.

B. Nature is the famous journal around the world.

C. Many endangered species are close to extinction.

D. Some rare species have appeared around the world.

2.From paragraph 4 we know that another future threat is .

A. destruction of habitats B. overfishing and pollution

C. the worsening climate change D. killing off wild creatures and plants

3.What is the real problem we are facing now according to paragraph 5?

A. The killing of wild creatures and cutting of trees.

B. The global warming caused by human beings.

C. The destruction of ocean ecosystem by pollution.

D. Evaluation of current rates of species' disappearances.

4.What does "This" in the last sentence refer to?

A. mass extinction. B. extinction rates.

C. extinction time. D. 75% of species or more.

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假設(shè)你是小明，請(qǐng)根據(jù)你校美化校園的規(guī)劃，用英語(yǔ)給你在美國(guó)的筆友Peter寫(xiě)一封信，介紹該規(guī)劃。信的主要內(nèi)容如下：

規(guī)劃目的： 美化校園、凈化空氣；創(chuàng)造良好的學(xué)習(xí)和生活環(huán)境

規(guī)劃內(nèi)容： 種植花草樹(shù)木；建一個(gè)植物園，供參觀、實(shí)踐；建一個(gè)小花園，供休息、讀書(shū)；建幾座名人雕塑，激勵(lì)師生

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2．詞數(shù)：100詞左右。

3．參考詞匯：雕塑—statue (n.) 植物園—botanical garden (n.)

Dear Peter,

I would like to tell you that our school has worked out a new program.___________________________________.

_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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● Measuring cup

● Wide-mouthed jar

● Salt

● Spoon

● Raw potato

You Will Do:

1. Pour 1.5 cups of warm water into the jar.

2. Add 1/3 cup of salt.

3. Stir(攪拌) until the salt is completely dissolved.

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5. Gently place the potato into the jar. Do not drop it.

What Will Happen:

The potato will sink— but only halfway!

Why?

Salt water is heavier than fresh water, so it will stay on the bottom. The fresh water will remain on top.

The potato is heavier than the fresh water, but it is lighter than the salt water. That is why the potato will sink halfway down.

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C. Step 3. D. Step 4.

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D. It will keep the liquids from mixing together.

3.In the experiment, what should you do right after you pour the water over the spoon?

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假定你是學(xué)生會(huì)主席李華，學(xué)校將舉行每年一次的18歲成人儀式，請(qǐng)你給外教Steven寫(xiě)一封電子郵件邀請(qǐng)他參加活動(dòng)。內(nèi)容包括：

時(shí)間：3月12日上午9點(diǎn)至11點(diǎn)

地點(diǎn)：學(xué)校大禮堂

對(duì)象：全體高三師生和家長(zhǎng)

活動(dòng)意義：內(nèi)容自定

注意：1.詞數(shù)100詞左右；

2.可以適當(dāng)增加細(xì)節(jié)，以使行文連貫；

3.開(kāi)頭語(yǔ)已為你寫(xiě)好。

參考詞匯：成人儀式coming-of-age ceremony; 禮堂auditorium

Dear Steven,

I would like to invite you to the annual Coming-of-age Ceremony of our school._______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________________________________________________________

Yours,

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