Across
- 1. a sign that shows someone is sick
- 3. a tall plant with hard hollow stems
- 5. an important task or job
- 7. having a point that can cut or hurt
- 11. a problem that delays progress
- 12. something that is most important
- 15. the outside part of something
- 19. easy to understand or do
- 20. a long thin piece of wood or metal
- 21. a person who designs or builds machines
- 22. a small shop or stand that sells goods
- 24. a substance in the body that fights disease
- 25. to send something into space
- 26. a small animal such as a mouse or rat
- 28. giving useful assistance
Down
- 1. dried stalks of grain plants
- 2. the act of bringing food back up from the stomach
- 4. a very small germ that can cause disease
- 6. a disease caused by germs entering the body
- 8. a living thing that another organism lives in or on
- 9. to push something with a finger or pointed object
- 10. a practice before an actual event
- 13. affected by a disease-causing organism
- 14. the period before symptoms of a disease appear
- 15. to put your foot down on something
- 16. to move from one place or person to another
- 17. a person trained to travel in space
- 18. a substance used to produce energy
- 23. a small amount of food eaten between meals
- 27. to make something happen later than planned