My uncle Tom is a famous scientist. He likes to make lots of predictions about the future. He says that in 100 years some things will be better than now. For example, we will not have to wash the dishes or sweep the floor because we'll all have robots in our homes. Also, we won't need to use paper money. We'll have more free time, and traveling will be faster and cheaper than it is now. Maybe some people will spend their vacations on space stations.
However, Uncle Tom says that some things will get worse in the next century. If more people use curs, there will be more pollution. Also, if there are fewer trees、the air will become dirtier. If pollution gets really bad, maybe people will have to go and live on Mars. Uncle Tom says we'll be very sorry if pollution becomes worse.
