The document discusses several dangers to the environment, including pollution, global warming, and extinction. It notes that human activities like agriculture, construction, and hunting can harm the environment. It also explains that pollution contaminates air, soil, and water from sources such as the combustion of coal and oil, insecticides, and industrial and urban waste. Additionally, the document outlines that the greenhouse effect occurs when the atmosphere traps heat, and increased carbon dioxide in the atmosphere is causing global warming and rising temperatures on Earth. This endangers many species and can lead to extinction.

1. DANGERS TO THE ENVIRONMENT
1. The environment
People affect the environment. The environment also affects people.
Some human activities, such as agriculture, construction and
hunting, can be harmful to the environment.
2. Pollution
Pollution is the contamination of air, soil or water.
 The combustion of oil or coal pollutes the air.
 Insecticides pollute the soil.
 Urban and industrial waste pollutes rivers and oceans.
 Pollution can change ecosystems.
3. Global warming
Carbon dioxide in the atmosphere maintains heat on the Earth. Life
on Earth is possible thanks to this heat. The atmosphere lets light in
but does not let heat out.This is called the greenhouse effect.
There is much more carbon dioxide in the atmosphere now.
Consequently, the Earth’s temperature is increasing because more
heat is retained in the atmosphere. This is called global warming.
4. Extinction
Pollution and global warming can cause species to become extinct.
Today many species are endangered.
All species depend on other species in food chains. Consequently, if
one species becomes extinct, other species can become extinct too.

2. Circle the correct alternative in each of the following sentences:
1. People affect / do not affect the environment.
2. Agriculture, construction and hunting can / can't be harmful to
the environment.
3. The greenhouse effect occurs when the atmosphere does not
let heat in / out.
4. There is much more / less carbon dioxide in the atmosphere
now.
5. The Earth's temperature is increasing /decreasing.
6. Today many / few species are endangered.