In the years leading up to the American civil war, tensions between the North and South, focused primarily on the issue of slavery, intensified. Many northerners sought a morally sound, unified labor system. Southerners, however, denounced free labor and advocated the expansion of the slave system. The ramifications of changes were unknown and threatening to both sides. The slave vs. free labor debate was particularly heated prior to the presidential election of 1860 when Abraham Lincoln and George Fitzhugh were among the most outspoken leaders. Lincoln maintained that free labor offered more protection to workers while Fitzhugh asserted that free labor was, in fact, more abusive and a greater threat to the well-being of workers.
GUQ Student Writing, 2008
Since the middle of the twentieth century, women in many countries have been seeking greater independence and opportunity.No longer content with their traditional roles as housewives and mothers, women have joined together to create what is known as the women's liberation movement. The impetus behind this movement varies from culture to culture, country to country, and individual to individual. In the United States, some of the major developments that led to the liberation of women were the creation of effective birth-control methods, the invention of labor-saving devices for the home, and the advent of World War II.
Adapted from Oshima, A. & Hogue, A. (1999). Writing Academic English (3rd ed.). White Plains, NY: Addison Wesley Longman, pp. 111-113