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Nowadays people are more aware that wildlife all over the world is in danger. Many species of animals are threatened, and could easily become extinct if we do not ___(1)___ an effort to protect them. There are many reasons for this. ___(2)___ some cases, animals are hunted for their fur or for other valuable parts of their bodies. Some birds, such as parrots, ___(3)___ alive and sold as pets. For many animals and birds, the problem is that their habitat - the place where they live - is disappearing. More land is used for farms, for houses or industry, and there are fewer open spaces than there once were. Farmers use powerful chemicals to help them grow better crops, ___(4)___ these chemicals pollute the environment and harm wildlife. The most successful animals on earth - human beings - will soon be the only ones left unless we can ___(5)___ this problem.