An industrial society, especially one as centralized and concentrated as that of Britain, is heavily dependant on certain essential services: for instance, electricity supply, water, rail and road transport, the harbors. The area of dependency has widened to include removing rubbish, hospital and ambulance services, and, as the economy develops, central computer and information services as well. If any of these services ceases to operate, the whole economic system is in danger.
　　It is this interdependency of the economic system that makes the power of trade unions such an important issue. Single trade unions have the ability to cut off many economic blood supplies. This can happen more easily in Britain than in some other countries, in part because the labor force is highly organized. About 55 per cent of British workers belong to unions, compared to under a quarter in the United States. For historical reasons, Britain's unions have tended to develop along trade and occupational lines, rather than on an industry-by-industry basis, which makes wage policy, democracy in industry and the improvement of procedures for fixing wage levels difficult to achieve.
　　There are considerable strains and tensions in the trade union movement, some of them arising from their outdated and inefficient structure. Some unions have lost many members because of industrial changes. Others are involved in arguments about who should represent workers in new trades. Unions for skilled trades are separate from general unions, which means that different levels of wages for certain jobs are often a source of bad feeling between unions. In traditional trades which are being pushed out of existence by advancing technologies, unions can fight for their members' disappearing jobs to the point where the jobs of other union's members are threatened or destroyed. The printing of newspapers both in the United States and in Britain has frequently been halted by the efforts of printers to hold on to their traditional highly-paid jobs.

　　21. Why is the question of trade union power important in Britain?
　　A. The economy is very much interdependent.
　　B. Unions have been established a long time.
　　C. There are more unions in Britain than elsewhere.
　　D. There are many essential services.

　　22. Because of their out-of-date organization some unions find it difficult to______.
　　A. change as industries change B. get new members to join them
　　C. learn new technologies D. bargain for high enough wages

　　23. Disagreements arise between unions because some of them
　　A. try to win over members of other unions
　　B. ignore agreements
　　C. protect their own members at the expense of others
　　D. take over other union's jobs

　　24. It is difficult to improve the procedures for fixing wage levels because______.
　　A. some industries have no unions
　　B. unions are not organized according to industries
　　C. only 55 per cent of workers belong to unions
　　D. some unions are too powerful

　　25. Which of the following is NOT TRUE?
　　A. There are strains and tensions in the trade union movement.
　　B. Some unions have lost many members.
　　C. Some unions exist in the outdated structure.
　　D. A higher percentage of American workers belong to unions than that of British workers.

　　答案：21. A 22. A 23. C 24. B 25. D