Uzupełnij zdania podanymi słowami w odpowiedniej formie.

1. Why do you think people cause so much ___ (destroy) to planet Earth?
2. In your opinion, what is the biggest ___ (environment) problem?
3. Is it ethical to try to reduce ___ (populate) in the world? Why (not)?
4. What ___ (danger) species do you know? What ___ (threat) ther habitats?
5. Is ___ (pollute) a serious problem where you live?