1.I am writing an English exercise now.
2. I was writing an English exercise at this time yesterday.
3. My little sister is sleeping now.
4. My little sister was slepping at this time yesterday.
5. My friends aren't doing their homework now. They are playing volley-ball. _ 6. My friends weren't doing their home¬work at seven o'clock yesterday. They were playing volley-ball.
7. Are you eating ice-cream now?
8. Were you eating ice-cream when I rang you up yesterday?
9. What your father is doing now?
10. What your father was doing from eight till nine yesterday?
11. Why is she crying now?
12. Why was she crying when I saw her yesterday?
13. She was reading the whole evening yesterday.
14. She isn't reading now.
15. Now she is going to school.
16. What are you doing now? —-I'm drinking tea.
17. Was you drinking tea at this time yesterday? — No, I wasn't drinking tea at this time yesterday, I was eating a banana.
18. My sister is fond of reading. She was reading the whole evening yesterday, and now she is reading again.
19. Look! My cat is playing with a ball.
20. When I went out into the garden, the sun was shining and birds were singing in the trees.