Across
- 2. the invention of this type of fan helps us stay cool in hot weather
- 3. a red light is an example of this and tells us to stop
- 6. something with many parts that can be hard to repair
- 7. something inventors use to test an idea
- 8. a good invention can have this type of problem
Down
- 1. someone known for his or her great mind
- 4. a light bulb is an example of this
- 5. a place where scientists may test their ideas using special equipment