Across
- 2. any animal in which the female gives birth to babies, not eggs, and feeds them on milk
- 4. a statement or proof that something is true
- 6. an important discovery or development that helps to solve a problem
- 10. someone who is a 100 years old or more
- 12. having a spine (=back bone)
- 14. a member of the most developed group of mammals (humans, monkeys, apes)
- 15. knowledge and understanding of a particular activity
- 19. a strong feeling of dislike or disgust
- 20. for granted to not realize or show that you are grateful for something or someone
Down
- 1. an area of land that is permanently frozen below the surface
- 3. a thing or a person that is very surprising or causes a lot of admiration
- 5. to grow again
- 7. causing disagreement or discussion
- 8. back bone
- 9. very forceful or energetic, healthy and strong
- 11. an amount of something that is available for use
- 13. to make something last longer
- 16. relating to creatures from another planet
- 17. to say an event or action will happen in the future
- 18. an arm or leg of a person or animal