Think of life in a desert: no food or water, only strong sun and heavy wind full of sand. You'd die of
thirst while waiting for a passing plane that never comes.
        But don't dismiss the thought as a nightmare (噩梦). Your hometown could become a desert if nothing
is done to prevent it.
        Deserts are eating land at high speed. In China, desertification (沙漠化) has affected 2,622,000 square
kilometres, equal to 14 Guangdong Provinces, mostly in the North. Deserts are advancing at a pace of 2,460
kilometres per year.
       According to the UN, one-third of the planet's land surface, with one billion people, has become desert.
Africa, Asia and Latin America have the driest land in danger of desertification.
        Recognizing the threat (威胁) to human beings, the United Nations has named 2006 the International
Year of Deserts and Desertification.
        It wants to increase public awareness (关注) of advancing deserts. Activities include a film festival in
Rome with films on life in unproductive (贫瘠的) lands. Meetings will discuss international cooperation, such
as planting trees and changing agricultural practices.
        Desertification takes place where rain is little and the climate hot. But human activities are the biggest
cause. Land turns into desert when the soil is over-farmed and too many animals eat up plants. To make
money, people also cut down trees that hold the soil. Desertification brings serious problems. From 1991 to
2000, droughts (干旱) killed over 280,000 people worldwide. When land becomes useless, there's a big loss
in food production.     
        Dust from deserts is blown into cities around the world. Each spring, Beijing is at risk of yellow dust
from the Gobi Desert. Dust from Africa reaches cities in the US and Europe, leading to illnesses and
worsening environments.

A. The bad influences of deserts.
B. How serious desertification is.
C. What makes land turn into desert.
D. The ways to change deserts into farms.

2. The purpose of writing the first paragraph is to _______.

A. serve as a picture of a large desert
B. show how important water is to humans
C. draw your attention to the problem of desertification
D. show how much is needed to be done to change deserts