—He lives alone. Most of the time, he is happy, but he feels ________ sometimes.

    The movie The Martian (《火星救援》) is very popular among space lovers. It shows an astronaut trying to live on Mars.

    Although the idea of living on Mars is great, the reality does not look so good. Mars does not have a friendly atmosphere (大气层) for humans. There is very little oxygen there. And because it is too far away from the sun, it is also very cold there. Sometimes the temperature on Mars can be -133℃. This is much too cold for humans.

    However, scientists say it might be possible to live there even without a good atmosphere. Daytime on Mars is almost the same as Earth's. It means there's enough sunlight to grow plants inside safe buildings. However, they would have to grow in soil from Earth. Mars does not have a strong enough atmosphere to stop the radiation (福射) coming from space, which makes it dangerous to grow things in the soil.

    The radiation also causes problems for our health. One way to live there is to build homes underground or in the rocks on the planet. This can help humans keep away from the radiation and keep warm.

    When could we live on Mars? Scientists are hoping to make it possible to live on Mars. Let's wait and see.

daughter during the rest of his life.

    ORBIS is an international charitable organization (国际慈善组织). Its main job (be) to help blind people all over the world.

    ORBIS uses a flying eye hospital (visit) poor countries. On the plane, volunteer doctors have operations (手术）on blind people.

    The plane is also used as teaching centre. Some doctors and nurses from poor countries can come to the plane to learn about eye (problem). Then they can help (many) blind people.

    ORBIS (train) and taught over 35,000 doctors and nurses so far. Every year they travel around the world (help) thousands of people. , they need your help to carry on with their work. For just $38, you can help one person see; for $380 you can bring light ten people; for $l, 300 you can help train a doctor. No matter how much money you can donate you're your love will help open their eyes to the world.