What I learnt in English Unit 9

I learnt that people might be able to live on mars in the future. People on Mars must use machines to recycle air and prevent the air from escaping. Scientists say that they will have to live in the spacecrafts that brought them there. The food they grow will have to be grown in greenhouses and people there will build inflatable houses.Actually, there are still many things about Mars but I cannot be possibly saying everthing! So, bye bye...