题目内容：

NASA’s twin Mars rovers, Spirit and Opportunity, have been exploring the Red Planet since 2004. But a little more than a year ago, NASA lost contact with Spirit. The space agency has tried several ways to make contact with the rover, but Spirit has not sent back any signals.

Spirit landed on Mars on January 4, 2004. Three weeks later, Opportunity arrived. Soon after, the rovers went to the opposite side of Mars. Spirit’s original mission was only designed to last for three months, but Spirit has worked for more than five years doing additional missions. Both rovers have made important discoveries about ancient Mars. They have taken thousands of images and found evidence in the rocks of a water, warmer past in Mars’ history.

Spirit is solar-powered. It got stuck in a sand trap in April 2009, trapped deep into the soil and with its wheels turning around and around but not able to move forwards or backwards. Spirit had to agree that there is nothing that can be done to change the situation—it’s never going to move again. However, even if it is a not moving station, it can still study the planet’s atmosphere and deep interior.

NASA has been concentrating on trying to position its solar panels to get as much energy from the sun as possible, or to get the rover leaning in a manner that will allow the most amount of sunlight falling on its solar panels, in order to keep it alive during the coming winter months. Engineers have planned to rock the vehicle back and forth to acquire a more favorable position. However, no matter how many efforts have been made, Spirit still could not get out of the soft soil and could not lean itself toward the sun as the Martian winter approached. Without enough energy reaching its solar panels and with so little energy in its batteries, it went into hibernation, just like a polar bear, and has not communicated with Earth since March 22, 2010.

Whatever the future holds for Spirit, its mission has been an outstanding success. When it landed on the Red Planet in January 2004, no one was really sure how long it would continue working in the cold and dusty environment. As a matter of fact, three months was its original goal.

After so many fruitless efforts, NASA scientists are losing hope of ever reconnecting with Spirit, but they will give it one more try. Ground controllers are contacting Spirit over a range of frequencies and at different times during the day in case its internal clock stopped working and it lost track of time. They also are commanding the rover to turn on its backup radio transmitter in case the main one is dead.

If this final effort to connect isn’t successful, NASA will shift the focus to its twin robot, Opportunity, which is in a different part of Mars. Opportunity is still on the move and continues to travel freely to this day. It has traveled 16.6 miles so far, and is currently rolling towards another crater it has yet to explore.

NASA has spent more than $900 million on the project but shows no sign of giving up on these determined and hard-working robots. The rovers are, though, experiencing gradual wear and tear, the expected damage to something caused by using it repeatedly over a period of time. Even before Spirit got trapped, one of its wheels had failed. And NASA says it’s just a matter of time before both robots break down completely.

1.According to the passage, what can we know about Spirit?

A. It had explored Mars several times.

B. Its original mission was to work for five years.

C. It landed on Mars three weeks later than Opportunity.

D. It discovered that Mars was once a warm and wetter place.

2.According to the passage, which of the following is NOT what NASA did?

A. Try to lean Spirit to make it get as much sunlight as possible.

B. Rock Spirit back and forth to make it acquire a more favorable position.

C. Make efforts to help Spirit get out of the soft soil where it is stuck.

D. Contact and order Spirit to turn on its backup radio transmitter.

3.The reason why Spirit failed to communicate with the Earth is that ________.

A. it didn’t have enough energy             B. it had finished its task

C. something was wrong with its wheels      D. it met an unidentified creature

4.By saying “NASA will shift the focus” in Paragraph 7, the author means that ______.

A. NASA will move the center of Spirit out of the sand

B. NASA will depend on Opportunity to do the exploration

C. NASA will do nothing but wait for some opportunity

D. NASA will make opportunity help Spirit

5.The last paragraph mainly informs us that _______.

A. NASA has planned to spend more money on Spirit

B. Spirit will be brought back to Earth

C. Spirit will stop operating totally in the future

D. Spirit will cause damage to Mars

6. What’s the text mainly about?

A. NASA makes the last effort to contact Spirit.

B. Spirit has made many important discoveries on Mars.

C. How Spirit got stuck and couldn’t move on Mars.

D. Why NASA tried many ways to contact Spirit.