Link the following sentences with: as a result, therefore, consequently or as a consequence. 1. Trees are being cut down. Many species will become extinct. 2. People in cities breathe exhaust fumes every day. Many of them develop breathing problems. 3. Industrial waste is dumped into the sea. Fish die. 4. People drop litter in the streets. People get diseases. 5. Most factories do not use filters. The air gets dirty.