Translation
Directions: In the following passage, there are five groups of underlined sentences. Read the passage carefully and translate these sentences into Chinese.  

     Machinery has made it possible to produce more and more food in vast areas, such as the plains of America and Russia. Crops have increased almost everywhere and people are growing more and more food. New forms of preservation have also been developed so that food need not be eaten as soon as it has grown.
     Progress in medicine and hygiene has made it possible for people to live longer. People in Europe and North America live, on the average, twice as long as they did a hundred years ago. In other countries, too, people generally live much longer than they once did. Babies, especially, have a far better chance of growing up because of increased protection against infant disease. However, all countries do not benefit to the same degree from this program in medicine and hygiene.
     In prehistoric time, people from Africa and Asia migrated to other continents. Europe was occupied by people from the East, America by groups from Asia. During the nineteenth and twentieth centuries, migrations have taken place within certain countries: the cities with their industries have attracted people away from the country. The possibility of earning a fixed salary in a factory or office was more attractive than the possibility of staying on the farm and having one’s work destroyed by frost, storms, or droughts. Furthermore, the development of agricultural machinery made it possible for fewer people to do the same amount of work.
     Thus, at the same time that the industrial revolution made it possible to produce goods more cheaply and more quickly in factories, and agricultural revolution also took place. Instead of leaving fields empty every third year, farmers began to plant clover or some other crop that would enrich the soil. Instead of using only animal fertilizer, farmers began to use chemical fertilizers to keep the soil rich. These methods have enabled French farmers, for example, to give five times as much wheat as was obtained from the same land two centuries ago.
     In many countries farmers find it more profitable to raise only one crop or one kind of animal. They choose the kind that gives the best results. Then they sell all that they produce, instead of trying to grow a little of everything and consume what they grow. This is a more feasible type of operation because modern methods and machinery are adapted to specific animals and specific crops. Therefore, it would be too expensive to do all the work by hand, or to buy the equipment needed for several different kinds of farming.