1 . The world got a glimpse（一瞥）of one of the greatest mysteries of our universe（宇宙）on April 10. That's when the first image of a black hole was shown to the public. The picture was created by a network of eight radio telescopes（射电望远镜）.

“We have seen what we thought was unseeable ,"says Shep Doeleman. He led the effort to create the image.

The black hole is at the center of galaxy（星系）named Messier 87,some 55 million light-years from the earth，and is 6.5 billion times the mass of the sun.

The image shows the gas，dust，and stars that move around the black hole before disappearing into it. It does not truly show the black hole，because not even light can escape its gravity. Black holes, like vacuums, suck（吸）in everything that gets too close.

根据短文内容，选择最佳答案。
1. In paragraph 1，the underlined word “image" probably means___________.

A．truth

B．fact

C．picture

D．information

2. In paragraph 2，the underlined sentence means seeing the black hole___________.

A．was expected before	B．was unexpected before
C．is common	D．is impossible

3. The black hole lies___________ the Messier 87 galaxy.

A．in the middle of	B．in the front of
C．at the back of	D．on the top of

4. What will probably happen if a spaceship gets close to the black hole?

A．It will fly around it.

B．It will be covered by the dust.

C．It will be sucked in.

D．It will be discovered.

5. What's the best title（标题）for this passage?

A．The Black Hole and its Gravity	B．First Look at the Black Hole
C．The Mystery of the Universe	D．Faraway Galaxy

2 . 请先阅读下面短文,掌握其大意,然后用方框中所给词的适当形式填空,并将答案填写到答题卡的相应位置。每个词限用一次。

know     life     different     back     and     interesting     sign     real     find     they

The planet Mars is the closest and most similar planet to Earth. It is very    1    to scientists. For example, Mars has seasons with    2    weather, but other planets have the same temperatures all year round. Was there    3    on Mars?

To find out, scientists need    4    if Mars ever had water. In 2004. two robot explores (探测器), or 'rovers', called Spirit and Opportunity were sent to look for    5    of water. These rovers can drive over rocks    6    all kind of rough ground. They can also use cameras and send photos    7     to Earth. First, the two rovers found chemicals and patterns (图文) in the rocks that were probably made by water. Then, they moved to another area and    8    other rocks which may have been created by water. Now scientists think there was probably water on the planet long ago. Today       9    are still not sure if there was life on Mars. They    10    need more information to decide. The discoveries of the two rovers answered some old questions, but they also brought up many new ones.

3 . After spending years searching for a planet with life, scientists may have found one. In September 2010, a team of US scientists discovered an Earth-sized planet called Gliese 581g. It has a surface temperature neither too hot nor too cold for liquid（液态）water. Scientists think there is a chance that the planet could have life.
The planet Gliese 581g goes around a star called Gliese 581, which is about 20 light-years from Earth. That is about 194 trillion（万亿）kilometres －500 million times farther away from us than the moon.
A spacecraft traveling at a one-tenth of the speed of light would reach Gliese 581g within about 220 years. A human can’t live that long, but robotic explorers could make the job easier. However, our fastest spacecraft don’t come anywhere near that one-tenth light-speed mark.
At present, scientists don’t know what the surface might be like on Gliese 581g. What they know is that the planet is at the sight distance from its star to have liquid water. It’s also at the right distance to have an atmosphere that could protect the water if it is on the surface.
Although spacecraft won’t be getting there anytime soon, one way to look for life on Gliese 581g is to turn our radio telescopes（望远镜）towards the planet and search for radiation（放射）. By studying the radiation, scientists would find out about the chemicals（化学物质）around the planet and discover it Gliese 581g has an atmosphere. If it has one, studying the atmosphere would give us a good idea if the planet has life or not. But it’ll probably be many years before we can do this properly.
People have been arguing about whether there is alien life on Gliese 581g. Any discussion about alien life is just guessing at this point, according to its discoverers.
1. What did scientists find in September 2010?

A．A planet with water.	B．A planet similar to the earth.
C．A planet without life.	D．A planet near the earth.

2. According to the article, Gliese 581g ________.

A．is at the right distance from its star	B．moves around the earth
C．is as far away from us as the moon	D．can be reached in about 220 years

3. Paragraph 5 is mainly about ______.

A．the possibility of living on Gliese 581g

B．the kinds of chemicals around Gliese 581g

C．the way of looking for life on Gliese 581g

D．the aim of studying the radiation on Gliese 581g

4. Which of the following is the best title for the passage above?

A．Gliese 581g, a Likely Living Planet	B．Gliese 581, a Likely Living Planet
C．Gliese 581g and Its Star	D．Gliese 581g and Radiation