Andy heard from his friend that a comet (彗星) was coming. He knew that a comet is a space rock. He wanted to watch it at 【小题1】 before sleeping.

When the evening came, it was a bit cold. So Andy 【小题2】 on a coat. He looked up in the sky. He could see the moon and some stars, but 【小题3】 new or special.

“Where is the comet? I only see the moon and some stars, ” he asked his friend on the phone. His friend told him where to look, 【小题4】 he still didn’t see it.

Andy went to wake his father up who was just 【小题5】 in the bedroom. Then Andy looked up in the sky 【小题6】 his father. Several minutes 【小题7】, they saw a fuzzy (模糊的) thing, which is bigger than a star. That was it.

“I think it would be like the moon or something, ” Andy said. “It's not big enough for that, and it might still be very 【小题8】 away from us,” his father said.

“I still wish I can see it better. ”

His father nodded and went inside. When he came back, he had a telescope(望远镜) in his hands. Through 【小题9】, they saw the comet a little better. It wasn’t much, but it helped.

After that night, Andy became interested in space and he thought being a(n) 【小题10】 must be cool! He wanted to go to the moon and even Mars on the spaceship one day.

Humans may live on another planet one day! That 【小题1】 (seem) impossible years ago. But now the idea may come true. According to Stephen Hawking, a British 【小题2】 (science), humans only have about 1,000 years to live on the earth. It means that humans 【小题3】 (fly) to another planet in 1,000 years. In fact, we have found one red planet Mars (火星). Experts have found that there 【小题4】 (be) water on it. The idea of living there looks possible. Thanks to science, the steps to Mars are getting 【小题5】 (fast) than before. For example, in 2013, Dutch experts 【小题6】 (plan) the first plan to put humans on Mars. They offered people one-way tickets to go and build a new home on Mars. 【小题7】 it was dangerous, over 200,000 people still wanted to take part in it. 【小题8】 the evening of September 21, US experts showed another plan to get humans to Mars in six years. They are also doing many 【小题9】 (prepare) to help people get back to the earth. I’m looking forward to 【小题10】 (live) on Mars. Will you join us?

There is nothing more i【小题1】 to life than the sun. W【小题2】 the sun, all living things on the earth would die. The sun is a star. In the sky there are t【小题3】 of stars like the sun. They are as large as the sun and as h【小题4】 as the sun. At night you can see many stars, but in the day you can only see one star—the sun.

The sun is much n【小题5】 to us than any other star. That is w【小题6】 it looks the biggest and brightest of all the stars. The distance (距离) of the sun from the earth is as m【小题7】 as 150,000,000 kilometers. Most stars are thousands of light-years a【小题8】 from the earth.

Do you know what a light-year is? N【小题9】 in the world travels faster than light. It travels 300,000 kilometers per second. And one light-year is the distance that light can travel in one y【小题10】.