It doesn't take long lo turnfarmlan

It doesn't take long lo turn
farmland into desert.
American farmers found this
out in the 1930s. They
planted wheat in large areas
of grassland in the south
central United States. For a
few years there was plenty of
rain and lots of wheat. Then
the rains stopped, as they
often do in this dry region.
The wheat dried up and the
top soil tumed to dust. Before
long, it had all blown away in
great dust storms. The area
became known as the "Dust
Bowl".
What happened in the Dust
Bowl is a perfect example of
erosion caused by modern
farming methods. Top soil
blows away more easily
when it is no longer protected
by grasses or trees. In ten
years or less, several feet of
good soil can disappear. And
once it is gone, there is no
way to get it back quickly. It
may takefrom one hundred
to a thousand years for new
top soil to form.
Unfortunately, it seems that
farmers have not learned
from the example of the Dust
Bowl. In the United States
alone, five billion tons of top
soil are lost every year.
Farmers continue to use the
same destructive methods.
They plant the same crops
and use tons of chemical
fertilizers.
The situation in other parts of
the world is even more
serious. The total loss of top
soil worldwide is 24 billion
tons a year. Areas of the earth
with a dry dimate (about one
third of the planet) are hit
worst. In these areas, about
12 million hectares of land
are lost to agriculture per year
because of erosion.
In developing countries, this
often leads to hunger and
death. The recent history of
one part of Africa, the Sahel,
is a good example. In the
1960s and 1970s much good
farmland was taken over for
export crops, such as sugar
and cotton. Many people
moved into the drier interior
areas to grovv their
food.During that period, there
was more rain than usual.
Food and cattle production
increased and so did the
population.
Before long, there were too
many people in these areas.
The land began to suffer the
effects. It was no longer
protected by trees, which had
been cut down for fírewood.
The grass and bushes were
gone, eaten by the eattle,
sheep, and other animals.
Animal manure was used for
burning instead of for
fertilizing the soil.
Then came a long period of
no rain. The ruined top soil
quickly blew away. The
Sahara Desert advanced in
some areas as much as 100
kilometers. In other areas,
the semi-desert land became
completely unproductive.
Now millions of people have
no way to make a living.
Many have died of hunger,
while others have moved to
the already crowded cities.
The events in the Sahel were
an important lesson for
government officials and
farmers around the world.
But again, the lesson has
been ignored. More and more
people are hungry on our
planet, but farmland
continues to be ruined.
This passage is
about________ .
According to the
passage, the "Dust Bowl"
_____ .
According to the
passage, the dust storms
________ .
The word “it” in
paragraph refers to _____ .
The word
“destructive” in paragraph 3
is closest in meaning to _____ .
We can infer from
this passage that chemical
fertilizers _____ .
The problem of
erosion is worst in ______ .
We can infer from
this passage that one
important factor in the Sahel
disaster was the______ .
The top soil in the
Sahel was ruined by _____ .
Many people in the
Sahel died of hunger because

Kết quả (Việt) 1:

It doesn't take long lo turnfarmland into desert.American farmers found thisout in the 1930s. Theyplanted wheat in large areasof grassland in the southcentral United States. For afew years there was plenty ofrain and lots of wheat. Thenthe rains stopped, as theyoften do in this dry region.The wheat dried up and thetop soil tumed to dust. Beforelong, it had all blown away ingreat dust storms. The areabecame known as the "DustBowl".What happened in the DustBowl is a perfect example oferosion caused by modernfarming methods. Top soilblows away more easilywhen it is no longer protectedby grasses or trees. In tenyears or less, several feet ofgood soil can disappear. Andonce it is gone, there is noway to get it back quickly. Itmay takefrom one hundredto a thousand years for newtop soil to form.Unfortunately, it seems thatfarmers have not learnedfrom the example of the DustBowl. In the United Statesalone, five billion tons of topsoil are lost every year.Farmers continue to use thesame destructive methods.They plant the same cropsand use tons of chemicalfertilizers.The situation in other parts ofthe world is even moreserious. The total loss of topsoil worldwide is 24 billiontons a year. Areas of the earthwith a dry dimate (about onethird of the planet) are hitworst. In these areas, about12 million hectares of landare lost to agriculture per yearbecause of erosion.In developing countries, thisoften leads to hunger anddeath. The recent history ofone part of Africa, the Sahel,is a good example. In the1960s and 1970s much goodfarmland was taken over forexport crops, such as sugarand cotton. Many peoplemoved into the drier interiorareas to grovv theirfood.During that period, therewas more rain than usual.Food and cattle productionincreased and so did thepopulation.Before long, there were toomany people in these areas.The land began to suffer theeffects. It was no longerprotected by trees, which hadbeen cut down for fírewood.The grass and bushes weregone, eaten by the eattle,sheep, and other animals.Animal manure was used forburning instead of forfertilizing the soil.Then came a long period ofno rain. The ruined top soilquickly blew away. TheSahara Desert advanced insome areas as much as 100kilometers. In other areas,the semi-desert land becamecompletely unproductive.Now millions of people haveno way to make a living.Many have died of hunger,while others have moved tothe already crowded cities.The events in the Sahel werean important lesson forgovernment officials andfarmers around the world.But again, the lesson hasbeen ignored. More and morepeople are hungry on ourplanet, but farmlandcontinues to be ruined.This passage isabout________ .According to thepassage, the "Dust Bowl"_____ .According to thepassage, the dust storms________ .The word “it” inparagraph refers to _____ .The word"phá hoại" ở đoạn 3là gần nhất trong các ý nghĩa để ___.Chúng ta có thể suy ra từđoạn văn này là hóa chất___ phân bón.Các vấn đềxói mòn là tồi tệ nhất trong ___.Chúng ta có thể suy ra từđoạn văn này là mộtCác yếu tố quan trọng trong Sahelthảm họa là the___.Đất hàng đầu trong cácSahel đã bị hủy hoại bởi ___.Nhiều người trong cácSahel chết đói vì