A. In B. During C. At D. For——青夏教育精英家教网—

In northern China during spring, big sandstorm often make trouble for people. Sandstorms usually happen in spring. They have happened in more than 10 provinces in northern China this year. People in southern China don't have to worry about this kind of bad weather. Most of the sand comes from the north of China. In northern China, lots of places have few trees and don't get much rain. When there aren't many trees, the ground can't keep enough water. Over the years, the ground dries up and turns to sand. When spring comes and the ice melts, the ground becomes loose. Strong winds take the loose sand into the sky. Besides, in northeast China, there lies some vast deserts.
Sandstorms are bad for people's health. If people breathe in too much sand, they will cough or have serious illnesses. Sandstorms also give farmers lots of problems. Sometimes their sheep get lost in the storms and never come back home. The winds also tear the farmers' houses down.
What can you do to stop sandstorms? Here's a piece of advice. Ask your parents to help you plant some trees this spring. If you see people cutting down too many trees, tell them about the dangers of sandstorms, and ask your government to stop them.
【小题1】When do sandstorms usually happen?

A desert is a very dry land where there is hardly any rain. In the day, it can be so hot that you could fry an egg on the ground. But during the night it is sometimes so could that water would turn into ice.

Many desserts are covered in sand. But some have mountains, rocks, or lakes that have dried up in the heat. The Great American Dessert has cliffs(悬崖) that have been made into amazing and beautiful shapes by the wind. The Sahara Desert in Africa is mostly sand. The Australian Desert has red sand.
Sometimes it does not rain for a whole year in the desert. But there is water deep under the ground and some plants have roots that go very deep to find it. Other plants have roots that spread out(延伸) a long way so they can suck up the rain as soon as it falls.
One desert plant is the cactus, which has long, spreading roots. The cactus stores water inside its hard skin. This skin protects it from heat and cold.
Camels are a bit like cactus plants! They store water too—inside their bodies. They have special fur which protects them from the sun during the day and keeps them warm at night.
Some other animals live in deserts, too. They have to be very good at seeing and hearing because most of them only come out at night. This is why many desert animals have extra big eyes or ears.
A desert fox has bigger ears than a normal for. A gerbil has huge eye, so that it can see at night. It stays cool in the day by staying underground, like most desert animals.
Some people live in the desert but they always make their homes near an oasis. An oasis is where water comes from an underground river. Near an oasis, people can grow lots of plants and keep animals.
Life is hard in the desert, for people, animals and plants. But desert people like to live there.
【小题1】A desert is very dry because__________.

A．it is sandy	B．there is so little rain
C．the wind is strong	D．there is no water deep under the ground

【小题2】What does the underlined phrase"suck up"in paragraph 3 mean_________?

【小题3】Some desert animals have extra big eyes or ears because__________.

A．the sunlight is too strong in the day	B．they need to see and hear well at night
C．it is very cold at nigh	D．they store water in them.

【小题4】Most desert animals stay cool in the day by_________.

A．storing water in side their bodies	B．drinking water as much as they can
C．staying underground	D．growing lots of plants

【小题5】Which of the following is true?

A．Desert people like to live in the desert though life is hard.

B．People in the desert usually fry eggs on the ground.

C．Camels have special fur to store water.

D．All the deserts are covered in sand.

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In old times，man considered lightning to be one of the great mysteries（神秘事物）of nature．In fact a single flash of lightning 1.6 kilometers long has enough electricity to light one million lamps．
The American scientist，Benjamin Franklin，was the first to suggest that lightning is in fact electricity formed between the earth and clouds high above．It happened in 1752．In the same year，he also built the first lightning rod（避雷针）to protect buildings from being struck by lightnings．
Modern science has discovered that lightning is very strong and powerful．A lightning between a cloud and the earth may be as long as 13 kilometers，and travels at a speed of 30 million meters per second．Scientists have the opinion that there are about 2000 million flashes of lightning per year．In the United States alone，it kills almost one person per day．
The safest place to be in during an electrical（电的）storm is a closed car．Outside，one should go close to low ground for cover and not stop under a tree．Also one should stay out of water and away from metal fences．Inside a house people should keep away from open doorways and windows and not touch wires or metal things．
【小题1】From this passage we know lightning is____．

A．one of the great mysteries of nature．

B．electricity high above the earth．

C．a kind of light．

D．the sound from the clouds．

【小题2】In the U．S____．

A．every person can see lightning every day．

B．at least one person is killed by lightning every day．

C．there are about 6 million flashes of lightning per year．

D．about one person per day dies from lightning．

【小题3】During a lightning storm，it would be best if you____．

A．stand under a tree．

B．go outside．

C．stay in a closed car．

D．stop near windows．

【小题4】A lightning rod can______．

A．prevent accidents caused by lightning

B．stop lightning

C．protect buildings from being washed away．

D．delay the coming of lightning

【小题5】A lightning between a cloud and the earth may be 13 kilometers long，and travels at
a speed of ______．

A．30 kilometres per second．

B．3000 kilometres per second

C．3 kilometres per second

D．30，000 kilometres per second

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During the day we work and play, and at night we sleep. Our bodies rest while we are 1 . In the morning we are ready 2 again. Our bodies grow 3 while we are asleep. Children who are tired usually 4 sleep. We can get better at our lessons 5 we have had plenty of rest. Boys and girls who are eight or nine years old need ten 6 sleep every night. Our bodies need plenty of 7 when we sleep. If we do not get enough fresh air, we 8 tired when we wake up. While in bed we must not cover our 9 . Our lungs(肺) needs to get 10 fresh air. If we 11 our windows at night, we can have plenty of fresh air. Cool air is better than warm air. Boys and girls who want to be 12 must get plenty of sleep.
Also, we need some after-school activities to keep in good health. 13 _students run every day. Some boys play basketball 14 a week. 15 girls, some often play volleyball….So good sleep and exercise can help us grow better and study better.

B．working and to play

C．to work and playing

D．working and playing

In old times，man considered lightning to be one of the great mysteries（神秘事物）of nature．In fact a single flash of lightning 1.6 kilometers long has enough electricity to light one million lamps．
The American scientist，Benjamin Franklin，was the first to suggest that lightning is in fact electricity formed between the earth and clouds high above．It happened in 1752．In the same year，he also built the first lightning rod（避雷针）to protect buildings from being struck by lightnings．
Modern science has discovered that lightning is very strong and powerful．A lightning between a cloud and the earth may be as long as 13 kilometers，and travels at a speed of 30 million meters per second．Scientists have the opinion that there are about 2000 million flashes of lightning per year．In the United States alone，it kills almost one person per day．
The safest place to be in during an electrical（电的）storm is a closed car．Outside，one should go close to low ground for cover and not stop under a tree．Also one should stay out of water and away from metal fences．Inside a house people should keep away from open doorways and windows and not touch wires or metal things．
【小题1】From this passage we know lightning is____．

A．one of the great mysteries of nature．

B．electricity high above the earth．

C．a kind of light．

D．the sound from the clouds．

【小题2】In the U．S____．

A．every person can see lightning every day．

B．at least one person is killed by lightning every day．

C．there are about 6 million flashes of lightning per year．

D．about one person per day dies from lightning．

【小题3】During a lightning storm，it would be best if you____．

A．stand under a tree．

B．go outside．