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　　Do you think that the population may be the greatest problem of the world today? 2000 years ago, the world’s population was very 　　1　　, there were not so many people．For several thousand years, it grew quite slowly．　　2　　 during the last three or four hundred years, it has grown very 　　3　　．Today it is growing faster 　　4　　 before．In one minute nearly 200 　　5　　 will be born in the world．Just think how many more there will 　　6　　 in a year．

　　A U．N．report said that the population of the 　　7　　 countries, like China and India, had been 1214 million in 1990．It is 　　8　　 that by the year 2050, the world’s population may be 9 billion．This means we must 　　9　　 much more food．We must have smaller families with 　　10　　 but healthier children．If we don’t do anything like that, there will not be enough space for anybody else to stand on the earth．