I. Open the brackets.
1. I have been sitting here for 20 minutes.
2. Tom has been working since 10 o'clock.
3. How long have you been studying English?
4. It has been snowing all day. When will it stop?
5. Jenny, the telephone is ringing. It has been ringing for a minute.
6. Since he came home, he has been watching TV.
7. What are you doing? – I am waiting for Alice. I have been waiting for her for 10 minutes.
8. It's nine p.m. Sue and Terry have been studying for 3 hours.
9. Since when had Alex been living in this house?
10. What have you been doing lately?
11. Marry is tired because she has been working in the garden.
12. is He still working at the same place?