Ex 2. Put the special questions.
0. He has been using my computer for 10 minutes. / Who has been using my computer for 10 minutes?
1. I have been waiting for you for more than an hour. 2. She has been reading since 3 o'clock. 3. I have been writing these sentences for an hour. 4. Mary has been watching TV since I returned. 5. They have been discussing this problem since 8 o'clock. 6. My sister has been playing the piano for half an hour. 7. It has been snowing since morning. 8. Somebody has been using my computer for 15 minutes, 9. The boys have been playing football. 10. He has been sleeping for more than two hours now.