第1个回答 2013-12-08
Our own planet,Earth,is becoming more and more crowded and polluted.Hopefully,we
can start again and build a better world on Mars.First of all,transport should
be much better.In a very short time,space shuttles will travel at half speed of
light.Humans meed food,water and air to survive.Scientists hope to plants that
can grow on Mars.These plants will produce the food and oxygen that we
need.However,it is not certain if these plants will be able to produce water
.The gravity on Mars is only about three-eights of the gravity on Earth.Humans
on Mars would have to wear special boots to make themselves heavir.