阅读理解。 Once very surprising, now very important, women astronauts (宇航员) explain what's so cool about zero-g, and what 50 years exploration (探索) has taught the world. Peggy Whitson Age: 48 Astronaut since:  1996 Space time: Two six-month tours on the Intemational Space Station, in 2002 and 2007-2008. 'Mind is a lot more important than body. So is your ability to think in 3-D and imagine how to move things in a different way than on earth. The second time I went to the station, it felt like coming home. I got comfortable much more quickly. Everything is lifted while you're up there, so you look younger. Being back on earth is not pleas ant at first. Moving around is difficult, like playing basketball. But I had my physical training for about a month after my retum.' Sunita Williams Age: 43 Astronaut since: 1998 Space time: Six months on the space station in 2006-2007, including more than 29 hours of space walks. 'I learned after about a week how to fly beautifully without going too fast or shaking around. I had a hard time remembering how to walk, I prefer flying! When you have that idea of being far away anti looking back at the planet, you don't see any cit- ies or countries. You see a very quiet place. Just as Gandhit-the Father of the Na- tion in India, once explained the feeling of oneness in all of us. Seeing our planet from space, you understand that.' Barbara Morgan Age: 56 Astronaut since: 1985 Space time: One shuttle mission in 2007 'No matter how I was situated (处于…位置) the first day, it seemed that my body was upside down (颠倒着). That might have been because all your blood comes to your head. And what memory do you have in that situation? It's like when you're kids, hanging upside down.' 1. What kinds of writing is the passage? A. A news report. B. A scientific article. C. A textbook lesson. D. A recorded interview. 2. How many of the mentioned women astronauts talked about zero-g? A. None. B. One. C. Two. D. Three. 3. What is the most serious problem astronauts may come across after they retum to the earth? A. They are still living a space life as usual. B. They are not used to the earth's situation. C. They are not as comfortable as in space. D. They are still thinking of their space travel. 4. What did Sunita Williams mainly leam by seeing the earth from space? A. Cities and countries are too small to be seen from space. B. We have only one earth, so we must protect our home. C. People in the world must come together as one family. D. The space is so big that the earth looks like a small ball.