The document discusses prehistoric times in North America, when it was covered in ice sheets during the last Ice Age. Due to lower sea levels, North America was connected to Asia by a land bridge where people first migrated from Mongolia at least 11,000-12,000 years ago. These early settlers crossed over from Siberia and entered Alaska in search of new hunting grounds, becoming the first inhabitants of North America.

1. Prehistoric Time
Many people have the impression that the U.S. has little
background and history. Other parts of the world are seen as having
ancient cultures and old civilizations. The USA, by contrast, is seen as
a recent discovery, a "new" world. Actually, the land and the people
that form the roots of American history stretch far back into the past. The U.S. of today
is only a small part of a long and colourful history.
The Ice Age. Tens of thousands of years ago, the Western Hemisphere
looked different than it does today. For one thing, it was much larger in size. At that
time, one-third of the earth's surface was covered by ice. This was the result of a
part of the earth's history known as the Ice Age. During the Ice Age, the general
climate of the earth slowly grew freezing cold. The moisture escaping from the
oceans and the seas, which usually returns as rain, fell mostly as snow. This
snow became packed into glaciers, or heavy, giant sheets of solid ice, which move
slowly across the land. With less rain falling, the oceans became lower than before,
and much of the earth that was normally covered by water became dry land.
The Land Bridge. The last Ice Age began 70 000 B.C., reached its peak about 40
000 B.C., and came to an end about 10 000 B.C. At different times during the last Ice
Age, glaciers covered much of Europe, Asia and North America. Because the oceans
were much lower than they are today, the western Hemisphere was much larger and
extended over a great portion of the globe. Southern America was much closer to
Africa, while North America was joined to Asia by a wide strip of land called a land
bridge. This land bridge is now covered by the Bering Strait.
Though the landmass of the Western Hemisphere was greater, the one
thing it lacked was people. Modern scientists claim that only giant
creatures, such as dinosaurs, roamed the frozen plains. There were no
humans to be found in this part of the world. It was not until the glaciers
started to melt, and the temperatures of the earth began to rise, that
humans made their first appearance on the continent.
Scientists believe that humans have been in North America at least 11000 or
12000 years. Who were the first people? By all accounts, the first settlers were from
Mongolia. They left their homes in what is now the Gobi Desert during the late stages
of the last Ice Age.
The Mongolians came there in search of better hunting grounds. Clothed in warm
skins and thick hides, they lived off the land and fought their way through hostile tribes
they met along the way. Finally, the wanderers reached the land bridge, crossed over
the Bering Strait from eastern Siberia, and entered the peninsula of Alaska.
I. Find answers to the following questions in the text:
1.Does the USA have little history?
2.How did the Western Hemisphere look like tens of thousands of years
ago?
3.What was the climate in the Ice Age?
4.Who were North America's first settlers?
5.Where did the people come from to the continent?
6.When did the ancestors of the Indians come to North America?
II.Say what information from the text seems important to you.
III.Find the words and expressions that mean the following: на самом
деле, напротив, в то же время, хотя, с одной стороны, по крайней мере,
по общим отзывам, в конце концов.