听力原文： Marriage is still a popular institution in the United States, but divorce is becoming almost as "popular". Nevertheless most American people get married at the present time. Fifty percent of American marriages end in divorce. However, four out of five divorced people do not stay single. They get married a second time to new partners. Sociologists tell us that in the twenty-first century most American people will marry three or four times in one life-time. Alvin Toffler, an American sociologist, calls this new social form. of serial marriages. In his new book Fortune Shock, Toffler gives many reasons for this change in American marriage. In modem society, people's marriages don't stay the same for very long. Americans frequently change their jobs, their homes: and their circle of friends. So, the person who was a good husband or wife ten years ago is sometimes not as good ten years later. After some years of marriage, a husband and wife can feel that their lives have become very different, and they don't share the same interest any more. For this reason, Toffler says, people in the twenty-first century will not plan to marry only one person for an entire lifetime. They will plan to stay married to one person for perhaps five or ten years, and then marry another. Most Americans will expect to have a "marriage career" that includes three or four marriages.
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A. Marriage that continues for many years without divorce.
B. Marriage that can easily end in divorce.
C. People will marry three or four times in one life-time.
Divorced people don't stay single.