Before the late 1800s, nearly all the people of Vietnam lived in villages, and the cultivation of wet rice was the principal economic activity. The basic component of rural society was the nuclear family, composed of parents and unwed children. As in China, however, extended family relationships were also important. In many cases, extended families lived together. Parents arranged the marriages of their children, and filial piety (obedience to one’s parents) was expected. Wives, too, were expected to obey their husbands. Families venerated their ancestors with special religious rituals. The houses of the wealthy were constructed of brick, with tile roofs. Those of the poor were of bamboo and thatch. Rice was the staple food for the vast majority, garnished with vegetables and, for those who could afford it, meat and fish. The French introduced Western values of individual freedom and sexual equality, which undermined the traditional Vietnamese social system. In urban areas, Western patterns of social behavior became increasingly common, especially among educated and wealthy Vietnamese. Elite Vietnamese attended French schools, read French books, replaced traditional attire with Western-style clothing, and drank French wines instead of the traditional wine distilled from rice. Adolescents began to resist the tradition of arranged marriages, and women chafed under social mores that demanded obedience to their fathers and husbands. In the countryside, however, traditional Vietnamese family values remained strong.