1) My father works at a factory. My father is working. Don't call him. My father has already been working here for many years.
2) Our teacher speaks on several languages. Our teacher has already been talking on the phone with the headmaster for 10 minutes.
3) He usually waits for me near the enterance. He has already been waiting for me till I finish writing the letter about an hour
4) It rains very often in autumn. Bring an umbrella. It has already been raining for 3 hours