| 1. | Children are usually full of energy. |
| 2. | What types of energy do you know? |
| 3. | What type of energy heats our houses? |
| 4. | Generator produces energy. |
| 5. | What powers the motor in this machine? |
| 6. | This is a high-powered engine. |
| 7. | How much is central heating nowadays? |
| 8. | What type of energy was used to heat buildings a century ago? |
| 9. | When was camera invented? |
| 10. | Is it your invention? |
| 11. | Who is the inventor of the wind-up technology? |
| 12. | Implant – is a very useful invention. |
| 13. | Before the invention of printing people had written books by hand. |
| 14. | People usually store information on their computers. |
| 15. | Energy can be stored and then used. |
| 16. | Storing energy was a very clever invention. |
| 17. | Solar energy is converted into electricity. |
| 18. | It’s cheaper to convert solar energy into electricity to heat buildings. |
| 19. | Japanese cars are usually very reliable. |
| 20. | Electrical power is unreliable in some countries. |
| 21. | People should care about the planet for future generations. |
| 22. | A new generation of implants has just been invented. |