11. Waves will be used as an____________ friendly source of energy. (environment)
12. Limit car trips by relying on biking, walking, public____________. (transport)
13. Solar power can be used to____________ or cool our houses. (hot)
14. Energy is used to____________ a lot of electrical things. (product)
15. There will be a____________ of energy in the near future. (short)
16. I don’t think so. The solar panels are becoming__________ and easy to install. (cheap)
17. Scientists are looking for clean and ____________ sources of energy. (effect)
18. I know it is also clean and safe to the environment. But does it cost a lot of money to install the____________ panels on the roofs? (sun)
19. More renewable energy sources will be used to solve the problem of_________. (pollute)
20. Because our major sources of energy are running out while the solar energy is abundant and____________. (limit)
21. ____________, fossil fuels are harmful to the environment. (fortunate)
22. Energy is used to produce a lot of____________ things. (electrical)
23. The____________ of wind turbines will be completed by next Friday. (install)
24. It can be found in only some places of the earth. It comes from____________ inside the earth. (deep)
25.____________ particles reach the Earth in just 8 minutes. (energy)