Check your english vocabulary for

Other words and expressions which you might find useful include:
For things going up: rocket / jump / edge up / soar / creep up / peak (especially for numbers, prices, etc.)
For things going down: slump / plunge / slip back / slip down / plummet / drop / bottom out (especially when talking
about prices) 
Page 6 How something works answers
1. thermostat (a heat controlling device in, e.g., a kettle or electric heater)    2. compact disc player    3. aerosol  
4. aeroplane (USA = airplane)    5. camera    6. food processor    7. firework
The other words in the grid are:
Kettle / computer / car engine / television / toaster / microwave oven / ballpoint pen / lightbulb / bicycle