题目内容

In dry weather the flowers will have to be watered if they _________．

[　　]
A．

have survived

B．

are to survive

C．

would survive

D．

will survive

答案：B
解析：

本题考查真实条件句，如果花要活下去的话，就必须浇水。A、C、D三项时态不对，are to survive并不是真正的将来时态，而是要表示预期、期望。故选B项。


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LONDON: What could possibly be wrong with planting trees? The advantages are obvious; they  firm the soil, soak up (摄取) extra water and take carbon dioxide (二氧化碳) out of the atmosphere.
However, it now turns out that planting trees could add to global warming.
Tree roots do a great job of keeping soil firmly on the ground and out of the wind’s power. The problem is that some of those dust clouds play an important part in soaking up carbon dioxide.
Huge dust storms blow out over the oceans from dry parts of North Africa and central Asia. Tons of dust are lifted and left as a thin film over the ocean surface. The dust fuels oceanic life.
Dust from China is carried east and left in the Pacific Ocean. If a tree-planting programme there is successful and the dust supply reduced, the net result may be that less carbon dioxide gets locked away in the ocean.
Andy Ridgwell, an environmental scientist from the University of East Anglia, has spent the past few years studying dust and says his work “shows clearly the complexity of the system and the importance of not tinkering(粗劣地修补) with it without understanding the results. For this reason there is the need to focus(集中) on cutting carbon dioxide giving off rather than monkeying (瞎弄) about with the land surface.”
An American scientist, Robert Jackson, has shown that when native grassland areas are invaded(侵入) by trees, carbon is lost from the soil. “We are studying why the soil carbon disappears, but one theory is that trees do a lot more of their growing above ground compared to grasses, so less carbon goes directly into the soil from trees, ” says Jackson.
In wet areas of the world, the gain from trees absorbing carbon dioxide above ground seems to be outweighed(超过) by the loss of carbon from the soil below ground. Countries that plan to combat global warming by planting trees may have to think again.
Solutions(解决办法) to environmental problems are often more complex than they first appear, and understanding the Earth’s climate is a very great challenge.
60．People usually hold the opinion that________
A．huge dust storms can destroy carbon dioxide
B．huge dust storms can destroy the oceans on the earth
C．huge dust storms can’t do anything beneficial for man
D．planting trees is the only way to control huge dust storms
61．Andy Ridgwell, the environmental scientist, believes that ________ .
A．dust plays a more important part than trees
B．trees shouldn’t have been planted in dry places
C．carbon dioxide is harmful to everything on the earth
D．environmental problems are more complex than expected
62．Robert Jackson’s experiment proves that________   .
A．grassland areas should be covered by forests
B．trees hold more carbon than grass
C．carbon can turn grass into dust
D．less carbon can make trees grow faster
63．The underlined word “combat” in the last paragraph means_______ .
A．learn about      B．fight against     C．live with   D．give up 

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
How to keep healthy? It’s easy for us to catch a cold in winter and spring because the weather changes a lot in spring and it is too cold in winter. But if we take care in our life, all of us can keep healthy without any cold.
    1    . This will stop germs（细菌,病毒） passing from one person to another. When you finish your work or before you eat, you’d better wash your hands.
    2     . Use a tissue（纸巾）, and then throw it into dustbins at once. When others around you are coughing, I advise you to turn your head away from the people so that their viruses won’t reach you.
Get more fresh air. Germs like staying around in dry and warm rooms.    3    . Don’t stay too long in the places with too many people.
If flu is going round house or school, you should try to stay away from those who are ill.    4   
Boil your toothbrush for about a minute. This kills germs .   5      . If you have used the toothbrush for three months or so, throw it away and buy a new one.

A. Have a shower every day
B. Wash your hands often
C. Don’t use your hands when coughing  
D. Don’t go out often when you are coughing
E. Besides, don’t use the same toothbrush too long
F. In this way, you won’t be infected by these people
G. you’d better stay in the places with more fresh air

The world economy has run into a brick wall. Despite countless warnings in recent years about the need to address a potential hunger crisis in poor countries and an energy crisis worldwide, world leaders failed to think ahead. The result is a global food crisis. Wheat, corn and rice prices have more than doubled in the past two years. And oil prices have increased more than three times since the start of 2004. These food-price increases, combined with increasing energy costs, will slow if not stop economic growth in many parts of the world and will even affect political stability. Practical solutions to these problems do exist, but we'll have to start thinking ahead and acting globally.

Here are three steps to ease the current food crisis and avoid the potential for a global crisis. The first is to promote the dramatic success of Malawi, a country in southern Africa, which three years ago established a special fund to help its farmers get fertilizer and seeds with high productivity. Malawi’s harvest doubled after just one year. An international fund based on the Malawi model would cost a mere $10 per person annually in the rich world, or $10 billion altogether.

Second, the U.S. and Europe should abandon their policies of paying partly for the change of food into biofuels (生物燃料). The U.S. government gives farmers a taxpayer-financed payment of 51 cents per gallon of ethanol (乙醇) changed from corn. There may be a case for biofuels produced on lands that do not produce foods — tree crops, grasses and wood products — but there’s no case for the government to pay to put the world’s dinner into the gas tank.

Third, we urgently need to weather-proof the world’s crops as soon and as effectively as possible. For a poor farmer, sometimes something as simple as a farm pond — which collects rainwater to be used in dry weather — can make the difference between a good harvest and a bad one. The world has already committed to establishing a Climate Adaptation Fund to help poor regions climate-proof vital economic activities such as food production and health care but has not yet acted upon the promise.

1. An international fund based on the Malawi model would______.

A. cost each of the developed countries $10 billion per year

B. give poor farmers access to fertilizer and highly productive seeds

C. decrease the food prices as well as the energy prices

D. aim to double the harvest in southern African countries in a year

2.With the second step, the author expresses the idea that ______.

A. we should get alternative forms of fuel in any way

B. it is misleading to put tree crops into the gas tank

C. it is not wise to change food crops into gas

D. biofuels should be developed on a large scale

3.Which of the following is true according to the passage?

A. The world has made a serious promise to build farm ponds.

B. A Climate Adaptation Fund has been established to help poor.

C. A rain-collecting pond is a simple safeguard against dry weather.

D. It makes a great difference whether we develop wood products or not.

4.In the passage, the author calls on us to______.

A. slow down but not to stop economy

B. act now so as to relieve the global food shortage

C. achieve economic growth and political stability

D. develop tree crops, grasses and wood products

 

请认真阅读下列短文，并根据所读内容在文章后表格中的空格里填入最恰当的单词。

注意：每空格1个单词。

For years, the automobile industry has been testing vehicles that use hydrogen as fuel. Now, people across the United States have had a chance to see and even drive cars that get power from hydrogen fuel cells (燃料电池).

But the hydrogen fuel cell is not a new idea. The fuel cell was first invented by Sir William Grove of Britain in 1839. Since then, many different designs, have been invented. There is one place where fuel cells are a proven technology: in space. The American space agency used fuel cells in its Apollo spaceships in the twentieth century.

The most useful fuel cell for transportation purposes is the Polymer Electrolyte Membrane, or P.E.M. fuel cell. It is simple and can operate at temperatures of sixty to eighty degrees Celsius. That is much lower than other fuel cell designs. A P.E.M. fuel cell has two sides divided by a thin membrane (膜). Hydrogen gas is forced through one side where it comes in contact with a reactive material containing the metal platinum(铂). The membrane separates the electrons(电子) from the protons(质子) in the hydrogen atoms. The protons pass through it to the other side of the fuel cell. But the electrons are captured to do work; like powering a motor. Oxygen from the air is forced into the other side of the fuel cell. There, the gas meets the protons that have passed through the membrane. They combine to form water and heat. A single fuel cell does not produce a lot of electricity. But when many fuel cells are combined, they can produce enough electricity to power a vehicle. The product of the chemical reaction that powers fuel cells is water. This makes fuel cells a very clean technology.

Hydrogen fuel cell cars have been slow to develop because of many technical problems that have to be solved. For example, it is unclear how long the membranes in P.E.M. fuel cells will last. Also, fuel cells need water for their chemical reactions. They must be designed to start easily at low temperatures and in dry climates. And smaller, less costly fuel cells must be designed before they can truly take the place of gasoline engines. Now more models of fuel cell vehicles are being tested than ever before. The threat of climate change and the high cost of oil have increased interest in these vehicles that do not cause pollution.

Title

 More Models of Hydrogen Cars Being Tested

The progress of hydrogen fuel cell

·1.________ by Sir William Grove in 1839.

·Designed 2.________ ever since.

·Used in Apollo spaceships in the twentieth century.

 Operating principle of P.E.M.

·It has two sides divided by a thin membrane.

·Hydrogen gas from one side 3.________ the active metal platinum.

·The electrons are 4.________ from the protons in the hydrogen atoms.

·The protons pass through the fuel cell to the other side.

·Oxygen from the air is5.________ into the other side of the fuel cell.

·The gas meets the protons，and then water and heat are6. ________

Reasons for slow 7.___________

of hydrogen fuel cell cars

·There are many technical problems8. ________

·The durability of the membranes in P.E.M. fuel cells is not clear.

·They have to start easily at 9.________ temperatures and in dry climates.

·They must be smaller and less costly before 10.________ gasoline engines.

 

 

 

     Along the river banks of the Amazon and the Orinoco there lives a bird that swims before it can fly, flies like a fat chicken, eats green leaves, has the stomach of a cow and has claws (爪) on its wings when young. They build their homes about 4.6m above the river, an important feature (特征) for the safety of the young. It is called the hoatzin.

      In appearance, the birds of both sexes look very much alike with brown on the back and cream and red on the underside. The head is small, with a large set of feathers on the top, bright red eyes, and blue skin. Its nearest relatives are the common birds, cuckoos. Its most striking feature, though, is only found in the young.

      Baby hoatzins have a claw on the leading edge of each wing and another at the end of each wing tip. Using these four claws, together with the beak (喙), they can climb about in the bushes, looking very much like primitive birds must have done. When the young hoatzins have learned to fly, they lose their claws.

      During the drier months between December and March hoatzins fly about the forest in groups of 20 to 30 birds, but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.

1．What is the text mainly about?

    A．Hoatzins in dry and rainy seasons.

    B．The relatives and enemies of hoatzins.

    C．Primitive birds and hoatzins of the Amazon.

    D．The appearance and living habits of hoatzins.

2．Young hoatzins are different from their parents in that        ．

    A．they look like young cuckoos

    B．they have claws on the wings

    C．they eat a lot like a cow

    D．they live on river banks

3．What can we infer about primitive birds from the text?

    A．They had claws to help them climb.

    B．They could fly long distances.

    C．They had four wings like hoatzins.

    D．They had a head with long feathers on the top.

4．Why do hoatzins collect together in smaller groups when the rainy season comes?

    A．To find more food.

    B．To protect themselves better.

    C．To keep themselves warm.

    D．To produce their young.

 

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