Теорія:

To speak about the problems of rare species, you need the appropriate vocabulary.
  
black-monkey-in-tree-holding-on-with-tail.jpg
 
Inflict on - to make someone suffer by doing something unpleasant to them;
 
Wipe out - to destroy something completely;
 
Evolution - the way in which living things gradually change and develop over millions of years;
 
Survive -  to continue to live after almost dying because of an accident, illness, etc;
 
Endangered - animals or plants which may soon not exist because there are very few now alive;
 
On the brink of extinction - on the point close to the situation when animals or plants will not exist;
 
Ivory - a hard, white substance from the tusks (= long teeth) of some animals, such as elephants (= large, grey animals);
 
Pesticide - a chemical that is used to kill insects which damage plants;
 
Toxic - poisonous;
 
Habitat - the natural environment of an animal or plant;
 
Ecosystem - all the living things in an area and the way they affect each other and the environment;
 
Reverse - to change a situation or change the order of things so that it becomes the opposite;
 
Wildlife - animals, birds, and plants living in their natural environment;
 
Deleterious - harmful.
 
Examples:
 
Tourism is damaging the fragile ecosystem of the reef.
  
Many species are on the brink of extinction.
  
Elephants were being hunted for their ivory.
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