Man cannot go on __1_ his numbers at the present rate, In the _2_ 30 years man will face a period of crisis. __3_ experts believe that there will be a widespread food_4_. Other experts think this is 5__ pessimistic, and that man can prevent things _6__ worse than they are now. But _7__ that two-thirds of the people in the world are undernourished or starving now. One thing that man can do is to limit _8__ of babies born. The need _9__ this is obvious, but it is _10_ to achieve. People have to _11__ to limit their families. In the countries of the population__12__, many people like big families. The parents think that this __13__ a bigger income for the family and ensures there will be someone in the family who will look __14__ them in old age. Several governments have _15__ birth control policies in recent years. __16__ them are Japan, China, India and Egypt. In some _17___ the results have not been 18__. Japan has been an exception. The Japanese adopted a birth control policy in 1948. People __19__ to limit their families. The birth rate fell from 34.3 per thousand per year to about 17.0 per year _20__. 

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