Across
- 3. A set of rules that explain how words work.
- 6. sometimes - not very often
- 7. how tall something is
- 9. simply
- 10. protect
Down
- 1. full of energy
- 2. the past
- 4. Scientists work in this way.
- 5. keeps us alive
- 8. The past tense of hear.
- 10. a collection