Today there are 6 billion people on the earth.

Today there are 6 billion people on the earth.
By the year 2050 there may be 12.5 billion.This means we need more food.
One way to produce more food is by growing stronger plants.For thousands of years,farmers have made
plants better.Every season,they pick the best plants for the next season.It works very slowly.Since 1983,
scientists have been able to change plants more quickly by changing their genetic material (遗传物质).Foods
from plants grown in this way are called genetically modified foods (转基因食品),or GM foods.
By changing the genetic material of a plant,it is possible to make new plants.They make plants which are
strong against plant diseases.They can also help in our diseases:a kind of rice is being prepared (准备),for
example,which stops people from becoming blind.
Rich countries produce GM food because they are easy to grow and bring in more money.Poor countries
are interested in them because they help produce more food.
GM plants are not natural.No one knows how good or bad they are.Making GM foods is only one way
of feeding people in 2050.There are strong feelings against them,because they are unnatural.They may feed
people,then hurt them or their children later.But,both rich and poor countries are very interested in their use,
and they are not going to go away.In 2050 we may think differently about them.
1.What will the population of the world be in 2050?
2.How did scientists change plants quickly?
3.what's the advantages of GM foods?
4.what's the disadvantages of GM foods?
5,Do all the people like GM foods?