1. Sheep - sheep
2. Baby - babies
3. Child - children
4. Green leaf - green leaves
5. Old lady - old ladies
6. Radio - radios
7. Ox - oxen
8. Tall woman - tall women
9. knife - knives
10. Toy - toys
11. Policeman - policemen
12. Raspberry - raspberries
13. Sandwich - sandwiches
14. Mouse - mice
15. Photo - photos
16. Cliff - cliffs
17. Pen - pens
18. Watch - watches
19. Big foot - big feet
20. Nice book - nice books