新编英美概况 许鲁之(第四版)Unit1-7课后习题简答题答案

Unit 1 Geographical Features and Natural Resources

1. How many states are there in the United States? And which two states are geographically separated from the others? (50, Alaska, Hawaii)

2. What are the general characters of the Rocky Mountains and the Appalachian Mountains.

1) To the west of Atlantic coastal plain lie the Appalachian Mountains that begin in Canada and reach all the way to Georgia and Alabama. These are old mountains with rounded tops and wooded hills, usually not exceeding 800m in height. The highest point is only 2000m above the sea. Most of the mountain ridges are low enough to be easily crossed by modern highways. The Appalachians have much beautiful scenery and many tourist resorts. The Ohio and the Tennessee Rivers flow down the western slopes of the Appalachians to the great Mississippi River, deep in the heart of America.

2) To the west of the Great Plains lie the Rocky Mountains, “the backbone of the continent”. These high mountains stretch all the way from Mexico to the Arctic and form what is known as Continental Divide, or Great Divide, the most important watershed on the continent. The Rockies are more than twice as high as the Appalachians and high enough to receive more rain than the surrounding plains and plateaus. Consequently, they are mostly forested. The striking and varied scenery of the Rockies has given rise to the establishment of many national parks here. The other natural wonders include roaming herds of buffalo, elk, deer, antelope and sheep, as well as the famous grizzly bear.

Chapter 2 American Population

1.Why is the United States known as a “melting pot”?

It means that the US is composed of immigrants from different nations all over the world.

①The people of the US are predominantly white.

②The second most numerous minority in the US were the black people whose forefathers came from

Africa.

③American Indians were the original inhabitants on the continent.

④There were about 50.5 million Hispanics in 2010 in the US. They are the Spanish-speaking immigrants

from Latin American countries.

⑤The Chinese American have proved to be industrious and intelligent.

2.What factors cause the Americans to move frequently within the United States?

①The desire for economic betterment is generally the most important force inducing migration.

②Geographic difference in economic opportunity, as reflected by such factors as differences in

employment opportunities and earning power for workers and differences in the availability and the price of land for farmers.

③Noneconomic factors. Such as climate, racial attitudes, and family tires, influencing migration.

3.Why do many Americans now migrate from cities to suburbs?

①The widespread uses of automobiles and the construction of express highways made it possible for

people to live farther away from their jobs.

②The telephone reduced the need for them to work or live in close proximity to one another.

③Suburban areas offered more living space than cities, lower crime rates, less pollution, and superior

schools. It is generally believed that they are better place for raising children.

Chapter 3 Discovery and Colonization of the New World

1. Discuss the pre-Columbian cultures in the Americas.

1) The Aztecs of Mexico

2) The Incas of Peru

3) The Indians of North America

4) Indian contributions to European culture: Foods, Drugs and Utilitarian objects

2. Why did the discoveries of New World before Columbus not exert great influence in the world at that time?