What is the sky？ Where is it？ How bright is it？ What lies above it？ These questions are difficult to answer, aren’t they？

　　Is the sky blue？ The sky has no color. We know that there is air around the world. When planes fly, they need air to lift their wings. Planes can’t fly very high because the air gets thinner when they go up higher. If we go up about 1,200 kilometers from the earth, we’ll find no air there.

　　When we talk about the sky, we usually mean the atmosphere around the earth. It is like a very thick “cover” over the earth and keeps it warm. Without the “cover”, the earth would be a very cold place and nothing could live on it.

　　Looking up above us, you will see the blue sky with white clouds. It is usually light blue, but the sky would be dark blue if you go to the top of the highest mountains. And you will see fewer clouds between you and the sun.

　　And if you sit in a spaceship high above the earth, there is no air at all. The sky would be so dark that its color would be black.

　　Sometimes the sky doesn’t look blue. When the sun rises and falls, you will see red, orange, and other colors in the sky. These are the most beautiful moments of the day.

　　Now you may understand that we see colors because the air scatters (散射) the sunlight. Light travels through the air. Without air, there would be no light and no colors.

1.Planes can’t fly very high because ____________.

A．there is air around the world

B．the air gets thinner when they go up higher

C．it’s warmer in the sky

D．the air gets thicker when they go up higher

2.We can see colors of the sky because ____________.

A．the sun rises and falls every day

B．the sky has lots of colors

C．the air scatters the sunlight

D．the sunlight has many colors

3.Which of the following is TRUE？

A．There is little air without light and colors in the sky.

B．The sky will look red, orange and other colors at noon.

C．The sky has only one color when the sun rises and falls.

D．The sky is dark blue if you go to the top of the highest mountains.

 

What do you think life on earth will（A）________in 100 years? More comfortable ?More high-tech? Maybe. But many scientists see a different future. （B） They say that by the year 2100 the earth will become a worse place for us to live.

   Greenhouse gases like carbon dioxide（二氧化碳）are warming up the earth, melting（熔化）ice, and raising the level of the oceans. All these changes may bring more disasters（ 灾难）,including earthquakes and floods（ 洪涝）.

   Sounds scary, doesn’t it? Luckily, things may become so bad. Most countries in the world have agreed to slow down earth warming.

   In February, the Kyoto Protocol （京都议定书）began.（C） 这是全世界141个国家间的协议。 They want to produce less greenhouse gas and slow the rising temperature. （D） By 2010,35 developed countries will cut greenhouse gas by 5 percent of the amount they produced in 1990. （E） In order to produce less greenhouse gas, countries have to use cleaner cars and fewer coal power stations. They also need to look for new types of energy（能源）.Countries that signed the agreement include China, Japan, Russia and the countries in the European Union（ 欧盟）.

1．在（A）的空白处填入一个适当的词语：________________

2．将划线部分（B）译成汉语：___________________________

3．将划线部分（C）译成英语：________________________

4．将划线部分（D）译成汉语：______________________________

5．将划线部分（E）改写为：Countries have to use cleaner cars and fewer coal power stations _____________they can produce less greenhouse gas.

When you look at the sky at night, the moon looks bigger than the stars. Actually, the moon is much smaller than the stars and the sun. It's much smaller than the earth. But the moon is much closer to us than any star. That is why it looks so big. If you hold a coin close to your eye, it looks big. If you look at it across the moon, it looks small.
The moon moves around the earth. It makes one trip in about four weeks. The moon looks flat to us. But it is a round ball, like the earth.
People once thought the moon had fire on it. They thought the fire made it bright. Now we know the moon is like a mirror. It gets its light from the sun.
Our sunlight comes from the sun, too. What is the sun? The sun is a star. The stars we can see have their own light. There are many big stars we cannot see. Their light had burned out. Others are still bright, but they are so far away that we cannot see them. The sun looks bigger and much brighter than other stars because it is the nearest of all stars. The sun and the other stars we see are very hot, but the air around us saves us from the heat of the sun.
The sun gives us light and warmth. It makes plants grow and turns leaves green. It makes life possible on our earth. It is a life giving star.
【小题1】 It takes _______ for the moon to go around the earth.

A．more than a week

B．nearly a month

C．half a year

D．more than a year

【小题2】 The moon is bright because _______.

A．there is some fire on it	B．it is near the sun, too
C．there is a big mirror on it	D．it can get light from the sun

【小题3】 The passage tells us _______.

A．the sun is not the biggest star	B．the sun is bigger than any other star
C．only the sun can shine	D．the sun is one of the farthest stars to us

【小题4】 Why do we call the sun "a life giving star"?

A．Because it gives us warmth.

B．Because there are some living things on it.

C．Because plants and animals can't live without it.

D．Because people have to live in the dark without it.

Imagine you are an astronaut, you find a new planet that looks like the earth, and when you want to put the flag on it, you find out that this planet has already got population. What would you do?
The US astronaut, Charles “Chuck” Backer, in the new cartoon film Planet 51 just comes across this thing.
Planet 51 is a place where there is no human being. So Chuck arrives in the planet and wants to name it “the US”. But he suddenly finds himself surrounded by lots of little green aliens.
These aliens live in fear that they may be invaded by strange being. They have never seen an alien until Chuck arrives. They think it is terrible and they get ready to defend themselves or attack Chuck. They send him to the Planet 51 Alien Invaders Space Museum. Chuck is very scared and tries to escape. The only thing he can do is to make his spaceship work and fly back to the earth. Luckily, he makes friends with a young alien named Lem. Then the adventure begins.
Planet 51 is a science fiction movie. It tells us that whether we are on the earth or in another society with aliens, we should accept the things that are different in our lives and experience them actively. In this way, we can grow up and understand ourselves better by changing.
The film is very funny and full of happiness. Will Chuck return home? If you want to know, see it!
【小题1】Charles “Chuck” Backer is a ___________.
A. US astronaut            B. green alien               C. US scientist
【小题2】When the green aliens see Charles “Chuck” Backer, they feel ___________。
A. excited                     B. scared                      C. sad
【小题3】What does the word “defend” mean in this passage?
A. 侵略                       B. 隐藏                       C.保护
【小题4】How can Chuck get out of the bad situation?
A. He must make friends with aliens there.
B. He must make the spaceship work and return to the earth.
C. He must destroy the Planet 51 Alien Invaders Space Museum.
【小题5】 What can we learn from the movie?
A. We shouldn’t explore or invade other planets.
B. We should learn to accept new things in order to improve ourselves.
C. We should experience more on the earth in order to be an astronaut.