Across
- 1. very useful or important
- 5. a very small amount of liquid that forms a round shape
- 8. a natural or man-made lake where water is stored
- 10. a sound or sounds produced through the mouth by a person speaking or singjing
- 11. a tube through which water or gases can flow
- 12. the amount or a number of sth.
Down
- 2. put sth. together with sth. else to increase the size, mumber, amount,etc.
- 3. a scientific test to study what happens and to gain new knowledge
- 4. from one end or side of sth. to the other
- 6. (water)with no salt
- 7. the act of travelling from one place to another
- 9. connected or operating; being used