UNIT 7
Lesson 49~56
Know Your World
Lesson 49:
The World Is a Big Place!Let's learn some geography!
Geography is the study of the world's places and population.
How many people are there in the world?
In the year 2000,the world's population was about six billion

people.
That's 6,000,000,000By 2025,
sicientists predict the world will have 7.8 billion people.
By 2050,there will be 9.1 billion people.
Where do all the people live?People live on land.
About one-third of the world is land.
There are seven continents:Africa,Asia,Australia,Europe,North

America,
South America and Antarctica.
Antarctica is the world's coldest and the world's driest

continent.
How many deserts does the world have?
Not all land is good for people.Some land is too dry.
This land is called desert.
Deserts cover one-fifth of the earth's surface.
How big are the world's oceans?
The world really has one big ocean,
but we have names for different pieces of it.
There are four main oceans:the Pacific Ocean,the Atlantic

Ocean,
the Indian Ocean and the Arctic Ocean.
Oceans cover about three-quarters of the earth's surface.
What's the world's biggest island?
The world's biggest island is Greenland.
Greenland is northeast of Canada.What's the world's longest

river?
The Nile River in Africa is the longest river.