We need energy to live and work. Our major source of (1) _____ is oil

Câu hỏi :

Read the passage and choose the correct answer A, B, C or D to complete the text.

We need energy to live and work. Our major source of (1) _____ is oil. Oil is one kind of fossil fuel. The amount of fossil fuels in the world is (2) _____. Therefore, we must save it and must find new sources of energy. Geothermal (3) _____ and nuclear power are alternative sources of energy. They can give us electricity. Other alternative sources are the sun, waves (4)_____ water. These sources are not only unlimited and available (5) _____ clean and safe for the environment. People should develop and use them more and more in the future.