1 . They will install solar panels on the roof of our house next week .
=> Solar panels will be installed on the roof of our house by them next week

2. Will the plumber check cracks on the water pipes in two days ?
=> Will the water pipes be cracked by the plumber check in two days ?

3. They won't show the film on types of future energy sources next Friday .
=> The film on types of future energy sources won't be showed by them next Friday

4. They will destroy the old power plant at the end of this year .
=> The old power plant will be destroyed by them at the end of this year

5. We will use biogas for cooking and heating next month .
=> Biogas will be used for cooking and heating by us next month

6. People won't burn fossil fuels for energy in the future .
=> Fossil fuels won't be burned for energy in the future

7. Shall we reduce our electricity bills to 20 % in five months ?
=> Shall our elctricity bills be reduced to 20% (by us) in five months ?

8. They will provide electricity next year .
=> Electricity will be provided by them next year

9. They will increase the tax on petrol to 15% next September .
=> The tax on petrol will be increased to 15% by them next September

10. We shall replace ordinary 100 - watt light bulbs with energy - saving ones .
=> Ordinary 100 - watt light bulbs with energy - saving ones shall be replaced by us