63. The experiment is carried cut to prove ______.

A. water pushes on your body when you swim underwater.

B. the earth is surrounded by a layer of air called the atmosphere.

C. the pressure of air around us has a powerful force.

D. the air pressure is not equalized around us.

答案  60.B  61.C  62.D  63.C

Passage 17

(09·辽宁C篇)

A volcanic eruption in Iceland has sent ash across northern Europe. Airlines have stopped or changed the flights across the Atlantic Ocean, leaving hundreds of passengers stuck in airports. 

Grirmsvom is one of the largest and most active volcanoes in Europe. What makes Grimsvom different is that it lies under a huge glacier(冰川) of ice up to 12 maters thick. The hot volcano heats up the ice above it, which then forms a layer(层)of water between the glacier and the volcano This layer of water puts pressure on the volcano, keeping it stable, As the water flows out from under the glacier, the pressure lifts. The lava(岩浆) from the volcano then comes up to the surface. This is exactly what happened today. 

Now, airlines have to make changes to their flights so as not to fly through the clouds of volcanic ash. According to KLM. one of Europe’s biggest airlines, airplanes cannot go under the cloud or over it. Going through the cloud can result in ash getting stuck in the airplane’s engines, causing damage to the plane. 

The eruption has also caused problems for animals in Iceland. The volcano left ash and sharp. Glass-like rocks all over the countryside. Farmers are keeping their animals inside to stop them from eating ash- covered grass to the sharp object. 

70.The underlined word “dissolve” is used to express the idea that organic matter and minerals from soil are      .

A.rushed away into the river

B.cleaned and purified by water

C.destroyed and carried away by water

D.mixed with water and become part of it

答案  67.B  68.B  69.C  70.D

Passage 16

(09·江西B篇)

The surprising experiment I am about to describe proves that air is all around you and that it proves down upon you. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth’s surface.

The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now foe the experiment!

What you need

·A hard-boiled egg without the shell

·A bottle with a neck slightly smaller than the egg

·A piece of paper

·A match

Metheod

1) Check that the paper will sit firmly on the neck of the bottle.

2) Tear the paper into strips and put the strips into the bottle.

3) Light the paper by dropping a burning match into the bottle.

4) Quickly sit the egg on the neck of the bottle.

Result

Astonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.

Why it happened

As the paper burns, it needs oxygen and uses up the oxygen (air) in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! The proves that air is all around and that it is pressing down on it.

59. Which of the following would be the best title for the passage?

A. Women Are Socially Trained to Talk     B. Talking Maintains Relationships

C, Women Love to Talk           D. Men Talk Differently from Women

答案  56.C  57.B  58.A  59.C

Passage 14

(09·江苏D篇)

Have you ever noticed the colour of the water in a river or stream after a heavy rainfall? What do you think caused this change in colour? It is soil that has been washed into the river from the riverbank or from t}le nearby fields.

Components of Soft

Soil is made up of a number of layers(层),each having its own distinctive colour and texture.The upper layer is known as the litter.It acts like a blanket.limiting temperature changes and reducing water loss.The topsoil layer is made up of small particles of rock mixed with rotten plant and animal matter called humus(腐殖质),which is black and gives the topsoil its dark colour.This layer is usually rich in nutrients,oxygen,and water.Below the topsoil is the subsoil,a layer that contains more stones mixed with only small amounts of organic matter.This layer is lighter in colour because of the lack of humus.Beneath the soil lies a layer of bedrock.

Soil forms from the bottom up.Over time bedrock is attacked by rain, wind,frost, and snow.It is gradually broken down into smaller particles in a process called weathering.Plants begin to grow,and rotten materials enrich the topsoil.Most of the soil in Eastern Canada.for example.Was formed from weathered rock that was exposed when the ice disappeared l2.000 years ag0.

Water Beneath the Soil

Surface water collects and flows above the ground in lakes.ponds.and rivers.Once in the soil or rock,it is called groundwater.Gravity pulls groundwater through the soil in a process called percolation(渗透).Eventually the water reaches a layer called the water table.Under this is bedrock through which water cannot percolate.

As water percolates downward,it dissolves organic matter and minerals from the soil and carries them to deeper layers.This causes a serious problem because plants require these nutrients for growth.

Soil pH

Soil can be acidic.neutral.or basic.The pH of the soil is determined by the nature of the rock

from which it was formed.and by the nature of t}le plants that grow and rot in it.

The acidity of rain and snow can lower the pH of the groundwater that enters the soil.By burning fossil fuels such as coal,oil and gasoline,humans have been contributing to higher levels of acidity in many soils.When fossil fuels are burned.gases are released into the air and then fall back to earth as acid rain.Acid soil increases出e problem of carrying nutrients to lower soil levels.As nutrients are removed,soil is less fertile.Plants grow more slowly in acidic soil,and also become easily attacked by diseases.

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