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A very important world problem is the growth of population on the earth. The population of the world today is more than 6,500,000,000. That is a great number and we know it quite well. ①The important thing is not how large the population of the world is now, but is the rate(速度) of the growth. It is about 1.63% every year after the number of dead people has been taken away.
To give you some ideas of the birth rate, look at the ②second handof your watch. Every second, four babies are born in the world. Another baby! Another baby! Another baby! Another baby! ③You can not speak quickly enough to keep up with the rate of the growth of the population. It is growing faster and faster. So it goes on, hour after hour. In one day, people have to find food for about 350,000 mouths more.
This great growth of population will make a big problem by the year 2050 — there will be as many as 7,500,000,000 people on the earth! So this is one of the biggest problems that you are going to meet in your life.
