Biogas is ….. and cheap for cooking and heating.

….. source of energy is the source that can’t be replaced after use.

Someone’s carbon …. is a measurement of the amount of carbon dioxide that their activities produce.

We must ….. the amount of water our family use every day.

Remember to ….. the lights before going to bed.

Wave energy is an ….. source of energy.

“Why is it called a …… source?” - “Because it can be replaced easily and quickly.”

Several governments try to …. the use of fossil fuels.

A hydropower station …. in the North of the country next year.

Low energy light bulbs should be used to ….. electricity.

We should put ….. on our roof for the heating and hot water.

If we go on …… electricity, we will have to pay a lot next month.

There are many available ….. power sources in Vietnam including sun, wind, water, etc.

Choose the best one (A, B, C or D) to complete the sentence

Nuclear energy is ……, but it is dangerous.

…. energy is produced by collecting sunlight and converting it into electricity.