题目内容：
根据以下材料，回答题Migrant (移民的) Workers
In the past twenty years, there has been an increasing tendency for workers to move from one country to another. While some countries have restricted most __________ (51) to local people,others have attracted and welcomed migrant workers. This is particularly the case in the Middle East, __________ (52) increased oil incomes have enabled many countries to call in outsiders to improve local facilities. Thus the Middle East has attracted oilworkers __________ (53) the U. S. A. and Europe. It has brought in workers from many countries, __________ (54) South Korea and Japan.
In view of the difficult living and worldng __________ (55) in the Middle East, it is not surprising that the pay is high to attract suitable workers. Many engineers and technicians can __________ (56) at least twice as much money in the Middle East as they can in their own country, and this is a major __________ (57)
Sometimes a disadvantage has a compensating ( 补偿的 )advantage. For example, the __________ (58)living conditions often lead to increased friendship when workers have to __________ (59) on each other for safety and comfort. In a similar way, many migrant workers can save large sums of money partly because of the __________ (60) of entertainment facilities. The work is often complex and full of problems but this merely __________ (61) greater challenge to engineers who prefer to find solutions to problems rather than do routine work in their home country.
One major problem which __________ (62) migrant workers in the Middle East is that their jobs are temporary ones. They are nearly always on __________ (63) , so it is not easy for them to plan ahead with great confidence. This is to be __________ (64) since no country welcomes a large number of foreign workers as permanent residents. In any __________ (65), migrant workers accept this disadvantage, along with others, because of the considerable financial benefits which they receive.
回答(51)题 A．cases
B．jobs
C．activities
D．uses
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