Поставить во множественное число / This is my computer. 2)He has a new suti. 3)This metal is very hard .4) That ship

1. These are our computers.
2. They have new suits.
3. These metals are very hard.
4. Those ships are Russian ones.
5. We heard their voices.
6. Their dogs don`t eat bread.
7. The plates were on the tables.
8. These towns are very large.
9. We were talking to them in the street yesterday.
10. Are those girls your sisters?
11. We shall give you our books.
12. These stories will be good ones.
13. Are these good matches?
14. The boys put their books on the desks.
15. They took off their hats.
16. Those houses are new.
17. The pupils put their books into the bags.
18. Are these students coming with us?