21. 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
22. Because our major sources of energy are running out while the solar energy is abundant and__________________. LIMIT
23. _________________ , fossil fuels are harmful to the environment. FORTUNATE
24. Energy is used to produce a lot of things. ELECTRICAL
25. The of wind turbines will be completed INSTALL
21. 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
22. Because our major sources of energy are running out while the solar energy is abundant and___unlimitted_______________. LIMIT
23. ____unfortunately_____________ , fossil fuels are harmful to the environment. FORTUNATE
24. Energy electricity is used to produce a lot of things. ELECTRICAL
25. The of wind turbines will be installed completed INSTALL
