Once it was possible to define male and female roles easily by the division of labor. Men worked outside the home and earned the income to support their families, while women cooked the meals and took care of the home and the children. These roles were firmly fixed for most people, and there was not much opportunity for women to exchange their roles. But by the middle of this century, men's and women's roles were becoming less firmly fixed. In the 1950s, economic and social success was the goal of the typical American. But in the 1960s a new force developed called the counterculture. The people involved in this movement did not value the middle-class American goals. The counterculture presented men and women with new role choices. Taking more interest in childcare, men began to share child-raising tasks with their wives. In fact, some young men and women moved to communal homes or farms where the economic and childcare responsibilities were shared equally by both sexes. In addition, many Americans did not value the traditional male role of soldier. Some young men refused to be drafted as soldiers to fight in the war in Vietnam. In terms of numbers, the counterculture was not a very large group of people. But its influence spread to many parts of American society. Working men of all classes began to change their economic and social patterns. Industrial workers and business executives alike cut down on 'overtime' work so that they could spend more leisure time with their families. Some doctors, lawyers, and teachers turned away from high paying situations to practice their professions in poorer neighborhoods. In the 1970s, the feminist movement, or women's liberation, produced additional economic and social changes. Women of all ages and at all levels of society were entering the work force in greater numbers. Most of them still took traditional women's jobs as public school teaching, nursing, and secretarial work. But some women began to enter traditionally male occupations: police work, banking, dentistry, and construction work. Women were asking for equal work, and equal opportunities for promotion. Today the experts generally agree that important changes are taking place in the roles of men and women. Naturally, there are difficulties in adjusting to these transformations. Which of the following best express the main idea of Paragraph 1? ______