Даю 35 баллов!!! Срочно!!!

Ответ:
1. It has been raining since three o'clock.
2. He has been playing chess since he was ten.
3. I have been working since eight o'clock.
4. Helen has been looking for a job for two months.
5. We have been waiting for two hours since we arrived
Объяснение:

It has been raining since three o'clock.He has been playing chess since he was ten.I have been working since eight o'clock.Helen has been looking for a job for two months.We have been waiting for two hours since we arrived