The Sahara

    The nameSaharaderives from the Arabic word for "desert" or "steppe". At 3. 5 million square miles，an area roughly the size of the United States，the Sahara Desert in northern Africa is the largest desert in the world. lt spans the continent from theAtlantic Oceanto theRed Sea. Daytime temperatures can reach as high as 130°F. The humidity sometimes gets into the teens. But it can also be as low as 2. 5 percent，the lowest in the world. Most of the Sahara receives less than five inches of rain per year，while large areas sometimes have no rainfall at all for years.

    At the heart of the Sahara is the landlocked north African country ofNiger. Here the sand dunes can be 100 feet tall and several miles long. Here sand plains stretch over an area larger thanGermanywhere there is neither water nor towns. Yet sitting in the midst of the surrounding desert is the town ofBilma. Suddenly there are pools of cIear water. Surprisingly，there are groves of date palms. Underground water resources，or oases，sufficient to support irrigated agriculture are found in dry stream beds and depressions. ¹Irrigation ditches run off a creek to water fields. ²  Corn，cassava，tea，peanuts，hot peppers，and orange，lime，and grapefruit trees grow in these fields. Donkeys and goats graze on green grass. ³

    The Sahara of Niger is still a region where you can see a camel caravan of 500 camels tied together in loose lines as long as a mile，traveling toward such oasis towns. There a caravan will collect life-sustaining salt，which is mined from watery basins，and transport it up to 400 miles back to settlements on the edges of the desert. The round trip across the vast sands takes one month.

词汇:

Humidity / hju:ˈmɪdəti / n. 湿度

irrigate / " lrlgelt/ v. 灌溉

stretch / stretʃ / v. 伸展

camel / "kæml / n. 骆驼

date palms n. 椰枣树

注释:

1. Underground water resources，or oases，sufficient to support irrigated agriculture are found in dry stream beds and depressions. 在干河床和洼地处可找到充足的地下水资源或者绿洲来支持灌溉农业。

2. Irrigation ditches run off a creek to water fields. 灌溉沟渠通过一条小溪到达水田中。

The phrase "an area roughly the size of the United States" gives an indication of the size of_______.

A:northern Africa B:Niger C:the Sahara D:all of Africa

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

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

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

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

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

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

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

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

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

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

The Family

    The structure of a family takes different forms around the world and even in the same society. The family"s 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. ¹ 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. ²  

    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. ³ 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 [ˈnju:kliə(r)] adj. 原子核的，中心的

harsh [hɑ:ʃ] n. 严酷的

emergency [ɪ"mɜ:dʒənsɪ] n. 紧急状况

agrarian [əˈgreəriən] 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。

The word mobility means_____.

A:money B:readiness to move C:organization D:skill