根据短文内容，从短文前的选项中选出能填入空白处的最佳选项。如果选项为E，则涂A和B两项。

A．There will probably be no school on Mars．

B．It might take us two or three days to get to Mars．

C．There is a problem for us to live on Mars．

D．Food will not be the same．

E．First, people will have more space．

Many people believe that, by the year 2100, we will live on the planet Mars(火星)．Here is what life could be like．

First of all, transport should be much better．By 2100, spaceship can travel at half the speed of light．　　1　　

Secondly, humans need food, water and air to live．Scientists should be able to find plants that can grow on Mars．These plants will provide us with food and air．

　　2　　 We could easily jump too high and fly slowly away into space．To prevent this, humans on Mars have to wear special shoes to make themselves heavier．

Life on Mars will be better in many ways．　　3　　 It is possible to live in a large building with many bedrooms．Then, robot will do most of the work, so we have more time for hobbies．

　　4　　 Every student can study, do their homework on the computer and take exams in online schools．Each student will also have their own online teacher called “e-teacher”．

However, in some ways, life on Mars may not be better than that on the earth today．　　5　　 Meals will probably be in the shape of pills(药片)and will not be as delicious as they are today．Also, space travel will make many people feel ill．