а) since. я так думаю "since"
1. Her hair is completely dark. They are very beautiful.
2. This news is very interesting. 3. Your money is on the table. Take them.
4. She is making progress in English.
5. She has enough knowledge to do the job.
6. Your pants are too long.
7. My glasses are on the table. Give them to me, please.
8. This year, fruit is very cheap.
9. There are oranges, bananas, grapes and other fruits on the table.
10. What news?- I am not satisfied with my progress in English.
11. Your advice is very useful. 12. Mathematics is a difficult subject.
13. The staircase is long and narrow.
14. There are a lot of people there. a difficult subject.
15. His clothes are dirty and wet. Wash it, please.
16. His knowledge is extensive.
17. Fruits are very healthy.
18. My watch is lagging, and I'm often late.
19. Please buy a bottle of milk, a loaf of bread and a couple of cakes.
He has been driving home from the airport since 6 o'clock
Удачи :)