. I (to write) an English exercise now. 2. I (to write) an English exercise at this time yesterday, 3. My little sister (to sleep) now. 4 My little sister (to sleep) at this time yesterday. 5. My friends (not to do) their homework now. They (to play) volley-ball. 6. My friends (not to do) their home¬work at seven o'clock yesterday. They (to play) volley-ball. 7. You (to eat) ice-cream now? 8. You (to eat) ice-cream when I rang you up yesterday? 9. What your father (to do) now? 10. What your father (to do) from eight till nine yesterday? 11. Why she (to cry) now? 12. Why she (to cry) when I saw her yesterday? 13. She (to read) the whole evening yesterday. 14. She (not to read) now, 15. Now she (to go) to school. 16. What you (to do) now? —-I (to drink) tea. 17. You (to drink) tea at this time yesterday? — No, I (not to drink) tea at this time yesterday, I (to eat) a banana. 18. My sister is fond of reading. She (to read) the whole evening yesterday, and now she (to read) again, 19. Look! My cat (to play) with a ball. 20. When I went out into the garden, the sun (to shine) and birds (to sing) in the trees.

1) am writing

2) was writing

3) is sleeping

4) was sleeping

5) aren't doing, are playing

6) weren't doing, were playing

7) Are you eating

8) Were you eating

9) is your father doing

10) was your father doing

11) is she crying

12) was she crying

13) was reading

14) isn't reading

15) is going

16) are you doing, am drinking

17) Were you drinking, wasn't drinking, was eating

18) was reading, is reading

19) is playing

20) was shining, were singing