What is the typical American family (21) ? Married American adults will name their husband or wife and their children (22) their "immediate family"(直系家庭). If they (23) their father, mother, sisters, or brothers, they will define them as separate units, usually (24) in separate households. Aunts, uncles, cousins, and grandparents are (25) "extended family"(扩大的家庭).The structure of the American family has undergone great changes (26) the 1950s. Traditionally, the American family (27) been a nuclear family, consisting (28) a husband, a wife, and their children. Grandparents (29) live in the same home with their (30) sons and daughters.In the 1950s, 70 percent of American households (31) the "classic" American family—a husband, wife, and two children. The father earned the money to 32 the family, the mother (33) the children and did not work outside the home, and they had two children.Yet, in the 1990s,only 8 percent of American households consisted of a (34) father, a stay-at- home mother, and two children. And 35 ,18 percent of households consisted of two parents who were both working and some or more children living at home.21.