Перед чем ставиться звук / s/ во мн.ч ?

1. a pen-two.............. 7. an ox-four.............
2. a bus-ten............... 8. a deer- two............
3. a woman-two......... 9. a child-two...............
4. a mouse-three........ 10. a class-three...........
5. a fish-three.............. 11. a foot-two.............
6. a tooth-five............. 12. a sheep-ten..........

1)A new house is in our street
2)Thialf story is very interesting
3)A woman a man a boy and a girl are in the room
4)in the farm-yard we see an ox a sheep a cow and a goose