Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors tend to promote social change by opening more areas of life to decision. In a society where people are quite similar in many ways, there are fewer occasions for people to see the need or the opportunity for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least customary and undisputed.
　　Within a society, social changes is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the less basic and less emotional aspects of society than in their opposites; in the simple elements rather than in the complex ones; in form rather than in substance; and in elements that are acceptable to the culture rather than in strange elements.
　　Furthermore, social change is easier if it is gradual. For example, it comes more readily in human relations on a continuous scale rather than one with sharp difference. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and their white counterparts.

　　21.The passage is mainly discussing.
　　A. the necessity of social change
　　B. certain factors that determine the ease with which social changes occur
　　C. two different societies certain factors that promote social change
　　D. One of the factors that tend to promote social change is.

　　22.A. joint interest B. different points of view
　　C. less emotional people D. advanced technology
　
　　23.According to the passage, which of the following is NOT true?
　　A. Social change tends to meet with more difficulty in basic and emotional aspects of society.
　　B. Disagreement with and argument about conditions tend to slow down social change.
　　C. Social change is more likely to occur in the material aspect of society.
　　D. Social change is less likely to occur in what people learned when they were young.

　　24. The expression "greater tolerance "(Para. 1) refers to_______.
　　A. greater willingness to accept social change
　　B. quicker adaptation to changing circumstances
　　C. more respect for different beliefs and behavior
　　D. greater readiness to agree to different opinions and ideas
　
　　25. Social change is less likely to occur in a society where people are quite similar in many ways because_______.
　　A. people there have got so accustomed to their conditions that they seldom think it necessary to change
　　B. people there have identical needs that can be satisfied without much difficulty
　　C. people there are easy to please
　　D. people there are less disputed

　　答案：21. B 22. B 23. B 24. C 25. A