英语四级(CET4)考试阅读考前练习题

　　Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1-7, choose the best answer from the four choices marked , , and . For questions 8-10, complete the sentences with the information given in the passage.

　　The Earth

　　Power and Light

　　Compared to the rest of the universe, the Earth is very small. Our planet and seven others orbit the Sun, which is only one of about 200 billion stars in our galaxy. Our galaxy, the Milky Way, is part of the universe, which includes millions of other

　　galaxies and their stars and planets. By comparison, the Earth is microscopic.

　　Compared to a person, on the other hand, the Earth is enormous. It has a diameter of 7,926 miles at the equator, and it has a mass of about 6 x 1024 kilograms. The Earth orbits the Sun at a speed of about 66,638 miles per hour . Dont dwell on those numbers too long, though; to a lot of people, the Earth is inconceivably, mind-bogglingly big. And its just a fraction of the size of the Sun.

　　From our perspective on Earth, the Sun looks very small. This is because its about 93 million miles away from us. The Suns diameter at its equator is about 100 times bigger than Earths, and about a million Earths could fit inside the Sun. The

　　Sun is inconceivably, mind-bogglingly bigger.

　　But without the Sun, the Earth could not exist. In a sense, the Earth is a giant machine, full of moving parts and complex systems. All those systems need power, and that power comes from the Sun.

　　The Sun is an enormous nuclear power source--through complex reactions, it transforms hydrogen into helium, releasing light and heat. Because of these reactions, every square meter of our planets surface gets about 342 Watts of energy from the Sun every year. This is about 1.7 ~ 1017 Watts total, or as much as 1.7 billion large power plants could generate. You can learn about how the Sun creates energy in How the Sun Works.

　　When this energy reaches the Earth, it provides power for a variety of reactions, cycles and systems. It drives the circulation of the atmosphere and the oceans. It makes food for plants, which many people and animals eat. Life on Earth could not exist without the Sun, and the planet itself would not have developed without it.

　　To a casual observer, the Suns most visible contributions to life are light, heat and weather.

　　Night and Day

　　Some of the Suns biggest impacts on our planet are also its most obvious. As the Earth spins on its axis, parts of the planet are in the Sun while others are in the shade. In other words, the Sun appears to rise and set. The parts of the world that are in daylight get warmer while the parts that are dark gradually lose the heat they absorbed during the day.

　　You can get a sense of how much the Sun affects the Earths temperature by standing outside on a partly cloudy day.

　　When the Sun is behind a cloud, you feel noticeably cooler than when it isnt. The surface of our planet absorbs this heat from the Sun and emits it the same way that pavement continues to give off heat in the summer after the Sun goes down. Our

　　atmosphere does the same thing-it absorbs the heat that the ground emits and sends some of it back to the Earth.

　　The Earths relationship with the Sun also creates seasons. The Earths axis tips a little-about 23.5 degrees. One hemisphere points toward the Sun as the other points away. The hemisphere that points toward the Sun is warmer and gets more light--its summer there, and in the other hemisphere its winter. This effect is less dramatic near the equator than at the poles, since the equator receives about the same amount of sunlight all year. The poles, on the other hand, receive no sunlight at all during their winter months, which is part of the reason why theyre frozen.

　　Most people are so used to the differences between night and day that they take them for granted.

　　But these changes in light and temperature have an enormous impact on other systems on our planet. One is the circulation of air through our atmosphere. For example:

　　The Sun shines brightly over the equator. The air gets very warm because the equator faces the Sun directly and because the ozone layer is thinner there.

　　As the air warms, it begins to rise, creating a low pressure system. The higher it rises, the more the air cools. Water condenses as the air cools, creating clouds and rainfall. The air dries out as the rain falls. The result is warm, dry air, relatively high in our atmosphere.

　　Because of the lower air pressure, air rushes toward the equator from the north and south. As it warms, it rises, pushing the dry air away to the north and the south.

　　The dry air sinks as it cools, creating high-pressure areas and deserts to the north and south of the equator.

　　This is just one piece of how the Sun circulates air around the world--ocean currents, weather patterns and other factors also play a part. But in general, air moves from high-pressure to low-pressure areas, much the way that high-pressure air rushes from the mouth of an inflated balloon when you let go. Heat also generally moves from the warmer equator to the cooler poles.

　　Imagine a warm drink sitting on your desk--the air around the drink gets warmer as the drink gets colder. This happens on Earth on an enormous scale.

　　The Coriolis Effect, a product of the Earths rotation, affects this system as well. It causes large weather systems, like hurricanes, to rotate. It helps create westward-running trade winds near the equator and eastward-running jet streams in the northem and southem hemispheres. These wind patterns move moisture and air from one place to another, creating weather patterns.

　　The Sun gets much of the credit for creating both wind and rain. When the Sun warms air in a specific location, that air rises, creating an area of low pressure. More air rushes in from surrounding areas to fill the void, creating wind. Without the Sun, there wouldnt be wind. There also might not be breathable air at all.

　　Water and Fire

　　The Sun has a huge effecton our water. It warms the oceans around the tropics, and its absence cools the water around the poles. Because of this, ocean currents move large amounts of warm and cold water, drastically affecting the weather and

　　climate around the world. The Sun also drives the water cycle, which moves about 18,757 cubic miles of water vapor through the atmosphere every year.

　　If youve ever gotten out of a swimming pool on a hot day and realized a few minutes later that you were dry again, you have firsthand experience with evaporation. If youve seen water form on the side of a cold drink, youve seen condensation in

　　action. These are primary components of the water cycle, also called the hydrologic cycle, which exchanges moisture between bodies of water and land masses. The water cycle is responsible for clouds and rain as well as our supply of drinking water.

　　注意：此部分试题请在答题卡1上作答;8-10题在答题卡1上。

　　1. How many Earths could fit inside the Sun?

　　One million.

　　93 million.

　　Two million.

　　100 million.

　　2. Earth would not have developed without __

　　water

　　fertilizer

　　soil

　　the Sun

　　3. What does our atmosphere do?

　　It absorbs the heat from the ground and sends it to the Sun.

　　It absorbs the heat from the Sun and emits it back to the Earth.

　　It absorbs the heat from the Sun and emits it the same way.

　　It absorbs the heat the ground emits and sends some of it back to the Earth.

　　4. __ receives about the same amount of sunlight all year.

　　The poles

　　The equator

　　The north temperate zone

　　The south temperate zone

　　5. Air rushes toward the equator from the north and south

　　because of the dry air

　　because of the cool air

　　because of the lower air pressure

　　because of the higher air pressure

　　6. What doesnt the Corolis Effect cause?

　　Westward-running trade winds.

　　Hurricanes.

　　The water draining from the sink.

　　Eastward-running jet streams.

　　7. The Sun has closely relation to create__

　　wind

　　the air

　　soil

　　fire

　　8. The Sun has a huge effect on___________.

　　9. If youve seen water form on the side of a cold drink, youve seen___________

　　10. The water cycle is responsible for clouds, rain and___________

　　文章精要

　　太阳对地球上万物的生命起着不可缺少的作用，这种作用主要表现在：为地球提供能量与光;地球自转与绕日公转形成昼夜交替与四季交替.同时出现相应的气候与天气变化;对地球上的水、海洋以及与之相关的循环起着至关重要的作用。

　　1.A根据题干信息词fit inside the Sun定位到第一个小标题下的第三段第三句and about a million Earths could fit inside the Sun。本题问，多少个地球才能把一个太阳填满，根据原文表述，100万个地球才能填满一个太阳，故本题选A。

　　2.D根据题干信息词developed without定位到第一个小标题下的倒数第：二段末句Life On Earth could not exist without the Sun，and the planet itself would not have developed without it，根据文章表述，如果没有太 阳，地球上的生命将不会存在，地球本身也不会发展到现在，太阳是地球存在发展的条件，题干中的 Earth即指原文中的the planet itself，故本题选D。

　　3.D根据题干信息词our atmosphere定位到第二个小标题下的第二段末句0ur atmosphere does the same thing-it absorbs the heat that the ground emits and sends some ofit back to the Earth。本题问，大气的作用是什么?根据文章表述，地球吸收来自太阳的热量然后释放，就像夏天里太阳落山后路面还持续放热一样，大气也在做同样的事吸收地面的热量，然后再把一部分返回到地面，故本题选D。

　　4.B根据题干信息词the same amount of sunlight定位到第二个小标题下的第三段倒数第二句This effect is... at the poles.since the equator receives about the same amount of sunlight all year，根据文章表述，赤道附近季节交替的变化不如两极那样显著，这是因为一年当中无论何时赤道所接收的太阳光都是没有变化的，与此相反，两极地区在冬季根本接收不到一点阳光，这也是那里为什么冰冻的原因，故本题选B。

　　5.C根据题干信息词air rushes和the equator定位到第二个小标题下的第七段首句Because of the lower air pressure, air rushes toward the equator from the north and south。根据文章表述，由于气压较低，空气从南 北部涌向赤道，在变暖的过程中上升，把干燥的空气推向南部和北部，故本题选C。

　　6.C根据题干信息词the Coriolis Effect定位到第二个小标题下的倒数第二段，根据文章表述，科里奥利效应作为地球上循环运动的产物，也影响着该系统，它能导致大规模的天气变化，如飓风、赤道附近的向西信风、南北半球的向东高速气流，由此可以排除A、B、D三项，故本题选C。

　　7.A根据题干信息词the Sun和create定位到第二个小标题下的最后一段首句The Sun gets much of the credit for creating both wind and rain。根据文章表述，太阳的一个重要作用是制造风和雨，has closely relation与gets much of the credit属同义转换，选项中没有rain，符合题干的只有wind，故本题选A。

　　8.our water。根据题干信息词a huge effect定位到第三个小标题下的第一段首句The Sun has a huge effect on our water。根据文章表述，太阳对我们地球上的水发挥着巨大作用，它温暖热带地区的海洋，又降低见不到太阳的两极地区的水温，在全球气候形成方面起着重要作用。

　　9.condensation in action。根据题干信息词water form，cold drink定位到第三个小标题下的第二段第二句It youve seen water form on the side of a cold drink， youve seen condensation in action。根据文章表述，如果你看到了冰冷的饮料旁边有一些水，事实上你看到的就是冷凝现象在发挥作用，这也是水循环的一个组成部分。in action意为在起作用、在运转。

　　10.Our supply of drinking water。根据题干信息词water cycle定位到文章最后一句The water cycle is responsible for clouds and rain as well as Our supply of drinking water。根据文章表述，水循环是云的形成及降雨的根源，还有我们的饮用水