X. Complete the expressions. Follow the model: since yesterday = for 24 hours; for 200 years = since the 19-th century. 1. since 1980
2. since Wednesday
3. since 6 o’clock p. m.
4. since December
5. since spring 10.
6. for 20 years
7. for 5 days
8. for the last 2 hours
9. for 6 months
10. for a very long time