名词变复数
1. box _________ 2. bus ________ 3. watch __________
4. brush _________ 5. orange ________ 6. page _________
7. hero_________ 8. kilo ________ 9. tomato _________
10. hippo(河马) __________ 11. baby _______ 12. family ________
13. key ________ 14. boy _______ 15. zoo _______
16. radio ________ 17. leaf _______ 18. knife _________
19. man ______ 20. woman _________ 21. sheep ________
22. tooth _______ 23. foot _______ 24. mouse _______
25. ox (公牛)________ 26. child _________ 27. Chinese ________
28. Japanese ________ 29. postcard_______ 30. hobby________