1) There are a lot of factories that POLLUTE the air with black smoke.
2) Water POLLUTION can kill animals and people.
3) People PRODUCE paper from wood. This leads to the DESTRUCTION of forests.
4) We must try to find a SOLVE to ecological problems.
5) People DESTROY wildlife and that's why a lot of animals become extinct.
6) The CONSTRUCTION of the new railroads can be dangerous for the
wild animals