1. A team of rescuers found three tourists who had disappeared after an avalanche.
2. There are a lot of animals which are under protection in Poland.
3. The tiger is an endangered species and may soon disappear if we don't protect it.
4. One of the most serious environmental problems is global warming.
5. Some households products contain chemicals which cause air pollution.
6. Hunting tigers is illegal in Russia and is therefore considered a crime.
