_____the damage is done, it will take many ye...

______the damage is done, it will take many years for the farmland to recover.

A.Until

B.Unless

C.Once

D.Although

高三英语单项填空中等难度题查看答案及解析

_____the damage is done, it will take many years for the farmland to recover.

A. Until　 　　　　　　　　 B. Unless

C. Once　 　　　　　　　　　 D. Although

高三英语单项填空中等难度题查看答案及解析

_____the damage is done, it will take many years for the farmland to recover.

A. Until　　 　　　　　　 　 B. Unless

C. Once　　 　　　　　　　 　　 D. Although

高三英语单项填空中等难度题查看答案及解析

_________ environmental damage is done, it takes many years for the ecosystem to recover.

A. Even if　　　　 B. If only　　　　 C. While　　　 D. Once

高三英语单项填空中等难度题查看答案及解析

______ environmental damage is done，it takes many years for the ecosystem to recover．

A．Even if　 B．If only

C．As if　 　 D．Once

高三英语单项填空简单题查看答案及解析

______ environmental damage is done，it takes many years for the ecosystem to recover．

A． Even if　　　　　　　　　　 B． If only

C． As if　　　　　　　　　　　　 D． Once

高三英语单项填空简单题查看答案及解析

Many jobs must be done with two people. One person takes the lead. The other helps. So it is with the human body. Much of our body depends on the cooperation between substances. When they work together, chemical reactions take place smoothly. Body systems are kept in balance.

Some of the most important helpers in the job of good health are the substances we call vitamins. The word “vitamin” dates back to Polish scientist Casimir Funk in 1912. He was studying a substance in rice. Funk believed the substance belonged to a group of chemicals known as amines (胺类). He added the Latin word “vita”, meaning life. So he called the substance a “vitamine”—an amine necessary for life.

Other studies found that not all vitamins were amines. So the name was shortened to vitamin. But Funk was correct in recognizing their importance.

Scientists have discovered 14 kinds of vitamins. They say vitamins help to carry out chemicals changes within cells. If we do not get enough of the vitamins, we are at risk of developing a number of diseases. This brings us back to James Lind of Scotland. In the 1740s, Lind was a doctor for the British Navy. He was investigating a problem that had existed in the Navy for many years.

The problem was the disease scurvy(坏血病). The sailors were weak from bleeding inside their bodies. Even the smallest wound would not heal. Doctor Lind thought the sailors were getting sick because they failed to eat some kinds of foods when they were at sea for many months.

Doctor Lind separated twelve sailors who had scurvy into two groups. He gave each group different foods to eat. One group got oranges and lemons. The other did not. The men who ate the fruit began to improve within seven days. The other men got weaker.

However, which foods should be eaten to keep us healthy? Let us look at some important vitamins for these answers.

1.Why was the name “vitamine” shortened to “vitamin”?

A. Because Funk was totally wrong.

B.Because few vitamins were amines.

C. Because there were new findings.

D. Because the latter was easy to remember.

2.The underlined word “This” in the fourth paragraph probably refers to that _______.

A. people tend to develop many diseases

B. lack of the vitamins causes disease

C. vitamins help chemical changes within cells

D. it is common for people to get no enough vitamins

3.Doctor Lind proved eating fruits can prevent scurvy by means of _______.

A. comparing　　 B. analyzing　　 C. surveying　　 D. questioning

4.What is the main topic of the passage?

A. Food to keep us healthy.

B. The benefits of vitamins.

C. Research into scurvy.

D. Facts about vitamins.

高三英语阅读理解中等难度题查看答案及解析

Your Car Is Ready for Take-off

The flying car has been talked about for many years，but now it appears that the idea is about to become a reality.

An international company has built a two-seater plane that, at the touch of a button ，transforms into a car perfectly suitable for driving on public roads. It has been designed so that the wings fold up automatically； and it takes just 15 seconds to switch between flying and driving. With its wings fully open and the propeller(螺旋桨）spinning, it can take off from any airfield.

Flying cars are quicker than traditional ones for travelling from city to city，and they can run on ordinary fuel. Another big advantage is that they are cool ，like something you would see in an action film. At the moment ₉ however, the flying car’s wheels are illegal to leave the ground. That is not because of technical reasons or problems with the design. It is because the various road and aircraft authorities simply cannot agree on whether it is a car or a plane.

“The government and the authorities have never thought seriously about a flying car, says Alan Price ，the president of the company that has developed it. “I wanted a car that could fly and drive ，but it is difficult to find an organization prepared to insure the vehicle against accidents.

Nevertheless _? the company hopes to produce and deliver its first flying car soon. The company already has orders for 40 of them. The majority the potential customers are older and some are retired。There have even been orders from some people who have no pilot's license.

The flying car will cost around $ 200_.000. “For an airplane _， that^’s a very reasonable price， but for a car, It's quite expensive，” explains Alan. “But it just is not possible to make a $ 10，000 flying car yet. ”

This latest means of transport will not become a mass-market item in the near future，but in the long term it has the potential to change the way you travel. It will become no more expensive than driving your car on the motorway. Travel time could be reduced by more than half.

So the next time you are told to fasten your seat belt, it may be to prepare for take-off.

1.We know from the passage that the flying car______

A．has to run on special fuel                 B．will replace traditional planes

C．is popular with the rich                   D．can shift between two forms

2.The flying car is presently forbidden to take off because______.

A．many people think driving it not very safe

B．it’s hard to decide whether it's a car or a plane

C．the government and the authorities don’t accept it

D．there are still some technical problems to be solved

3.We can learn from the passage that______.

A．few people will be able to afford a flying car

B．flying cars may share the market in the future

C．traffic jams will disappear because of flying cars

D．driving a flying car doesn’t require a pilot’s license

高三英语阅读理解中等难度题查看答案及解析

The year 3700, Earth is far too hot for any human to call it home. On this planet at least, man is nothing more than a memory--if there is anything left to remember the "wise man". But what about our wisdom--will any of it survive us?

The conventional answer is no. Knowledge requires a knower, and there will be no knowing minds around then. But if information survives, perhaps in books or hard drives, maybe the knowledge isn't quite dead but dormant(休眠), ready to become alive with the help of other minds that develop over time or come to visit Earth in the distant future.

At first sight, that seems to be reasonable: after all, we have done similar things with past knowledge. For example, we saved an ancient computer from a ship destroyed at sea off the southern coast of Greece, and succeeded in finding the meaning of Egyptian hieroglyphics(象形文字). Careful work can bring previously lost wisdom back to life.

However, the key point is that there is a certain cultural continuity with those ancient times that allows us to reason and make progress in the dark: we know we are dealing with the legacy(遗产)of other humans. Without that link, the survival of objects and raw data doesn't guarantee the survival of knowledge. And a lack of continuity in language with any future intelligence would be a barrier. Knowledge is closely connected with language. When a language dies out, we can lose systems of reasoning that they contain. If that's lost, then it can't be recovered.

All this means that other minds might not be able to fully make human knowledge alive when we are gone. It is better to concentrate on not dying out in the first place.

1.How many opinions are mentioned in Para.2?

A. One.

B. Two.

C. Three.

D. Four.

2.What does the underlined phrase "similar things" in Para. 3 probably refer to?

A. Making lost wisdom alive again.

B. Rescuing disappearing knowledge.

C. Preserving future knowledge.

D. Gaining new knowledge.

3.How can we make knowledge survive?

A. We know a lot about human beings.

B. We learn ways to draw conclusions.

C. We have a certain cultural continuity.

D. We protect the legacy of other humans.

4.What's mainly talked about in the text?

A. Can human beings live on?

B. Will our knowledge survive us?

C. What will the earth be like in the future?

D. How can we protect our culture?

高三英语阅读理解中等难度题查看答案及解析

The year 3700， Earth is far too hot for any human to call it home． On this planet at least， man is nothing more than a memory - if there is anything left to remember the"wise man"． But what about our wisdom -will any of it survive us？

The conventional answer is no． Knowledge requires a knower， and there will be no knowing minds around then． But if information survives， perhaps in books or hard drives， maybe the knowledge isn't quite dead but dormant （休眠）， ready to become alive with the help of other minds that develop over time or come to visit Earth in the distant future．

At first sight， that seems to be reasonable： after all， we have done similar things with past knowledge． For example， we saved an ancient computer from a ship destroyed at sea off the southern coast of Greece， and succeeded in finding the meaning of Egyptian hieroglyphics（象形文字）． Careful work can bring previously lost wisdom back to life．

However， the key point is that there is a certain cultural continuity with those ancient times that allows us to reason and make progress in the dark： we know we are dealing with the legacy （遗赠） of other humans．

Without that link， the survival of objects and raw data doesn't guarantee the survival of knowledge．And a lack of continuity in language with any future intelligence would be a barrier． Knowledge is closely connected with language． When a language dies out， we can lose systems of reasoning that they contain． If that's lost， then it can't be recovered．

All this means that other minds might not be able to fully make human knowledge alive when we are gone． It is better to concentrate on not dying out in the first place．

1.What is the main purpose of Paragraph 1？ ______

A. To present an interesting idea．

B. To state a problem of the future．

C. To inform us of the earth in 3700．

D. To introduce the topic of the text．

2.What do the words"similar things"in Paragraph 3probably refer to？ ______

A. Developing the minds．

B. Remembering the wise man．

C. Making lost wisdom alive again．

D. Learning from the ancient civilization．

3.What plays the key part in getting cultural continuity according to the text？ ______

A. Language．　　 B. Intelligence．

C. Knowledge．　　 D. Information．

4.What can be the best title for the text？ ______

A. Can human beings live on？

B. Will our wisdom survive us？

C. How we can protect our culture

D. What the earth will be like in the future

高三英语阅读理解困难题查看答案及解析