Across
- 2. dry
- 6. paper
- 9. astronaut
- 12. planet
- 13. sea
- 17. solar system
- 18. recycling
- 21. valley
- 23. nature
- 24. sky
- 27. bird
- 28. moon
- 29. leaf
- 30. desert
- 33. garbage
- 35. star
- 39. geography
- 42. flower
- 43. continent
- 44. city
- 47. environment
- 48. town
- 49. throw away
- 50. tree
- 51. sun
Down
- 1. island
- 3. ocean
- 4. plastic
- 5. metal
- 7. province
- 8. air
- 10. border
- 11. capital
- 14. water
- 15. comet
- 16. country
- 19. insect
- 20. container
- 22. eclipse
- 25. mountain
- 26. forest
- 31. fish
- 32. glass
- 34. universe
- 36. earth
- 37. recycle
- 38. plant
- 40. animal
- 41. region
- 45. lake
- 46. river