The structure of a family takes different forms around the world and even in the same society. The familys form changes as it adapts to changing social and economic influences. Until recently, the most common form in North America was the nuclear family，consisting of a married couple with their minor children. The nuclear family is an independent unit. It must be prepared to fend for itself. Individual family members strongly depend on one another. There is little help from outside the family in emergencies. Elderly relatives of a nuclear family are cared for only if it is possible for the family to do so. In North America，the elderly often do not live with the family ; they live in retirement communities and nursing homes.
There are many parallels between the nuclear family in industrial societies，such as North America，and of families in societies such as that of the Inuits，who live in harsh environments. The nuclear family structure is well adapted to a life of mobility. In harsh conditions，mobility allows the family to hunt for food. For North Americans，the hunt for jobs and improved social status also requires mobility.
The nuclear family was not always the North American standard. In a more agrarian time，the small nuclear family was usually part of a larger extended family. This might have included grandparents，mother and father，brothers and sisters，uncles，aunts，and cousins. In North America today，there is a dramatic rise in the number of single-parent households. Twice as many households in the United States are headed by divorced，separated，or never-married individuals as are comprised of nuclear families. The structure of the family，not just in North America, but throughout the world，continues to change as it adapts to changing conditions.
词汇:
nuclear /nju:kh/ adj. 原子核的，中心的 harsh /ha: / n. 严酷的
emergency /Im :d nsI/ n. 紧急状况 agranan / gre rl n/ adj. 土地的，耕地的
注释:
1. lt must be prepared to fend for itself. 它必须能够照料自己。
2. In North America，the elderly often do not live with the family; they live in retirement communities and nursing homes. 在北美洲，老人很少和家人一起生活;他们一般住在退休社区和养老机构。
3. In harsh conditions，mobility allows the family to hunt for food. :在恶劣的条件下，流动性能让一个家庭吃饱饭。
练习:
1. Another good title for this passage would be_____.
A) What Makes a Family?
B) The Life of the Inuits.
C) Living with Hardship.
D) The Failure of theNuclear Family.
2. A nuclear family is defined as_____.
A) a married couple with their minor children
B) a single father with，minor children
C) parents，grandparents，and children
D) parents，children，and aunts and uncles
3. The information in this passage would most likely be found in_____.
A) an anthropology textbook
B) a biology textbook
C) a mathematics textbook
D) a geography textbook
4. The information in the first paragraph is presented mainly through _____.
A) listing statistics
B) telling a story
C) pointing out similarities
D) pointing out differences
5. The word mobility means_____.
A) money
B) readiness to move
C) organization
D) skill
答案与题解:
1. A 本题问的是:这篇文章的题目还可以是什么? A 的意思是是什么构成了一个家。B 的意 思是因纽特人的生活。C 的意思是生活得很艰难。D 的意思是核心家庭的失败之处。根据文意，本文主要介绍了与家庭相关的信息。B 不是主要内容。C 未提到。D 未提到。因此A 是正确的答案。
2. A 本题问的是:核心家庭的定义是什么?根据第一段的第三句话:Until recently，the most common form in North America was the nuclear family，consisting of a married couple with their minor children. 可知 A 是正确的答案。
3. A 本题问的是:这篇文章最有可能出自哪里? A 的意思是人类学课本。B 的意思是生物课本。C的意思是数学课本。D 的意思是地理课本。本文主要介绍了家庭，因此最有可能是人类学课本。所以 A 是正确的答案。
4. C 本题问的是:第一段的信息主要以何种方式陈述的?根据第一段的陈述方式，并没有列 出数据或者讲故事，而是通过描述共性而阐述出核心家庭的概念。因此 C 是正确的答案。
5. B 本题问的是:mobility 的词意。Mobility 是 mobile 的名词形式。根据文中第二段，核心家庭能够生存下去最重要的是能够有流动性，而钱、组织或是技能都不是能够使一个家庭吃饱饭的必要条件。因此 B 是正确的答案。