1 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
Every day we use energy. We use it for cooking, for heating and for lighting our cities. The energy comes from many different 1 (source). It can come from the sun, wind and water, but the energy we depend on the most comes from deep inside the Earth. These include coal, oil, and natural gas.
These fuels come from the remains of plants and animals. It takes millions of years 2 (make) them. However, with the world’s population 3 (grow), more and more of these fuels are dug up from the ground. Yet these fuels are non-renewable. When they 4 (use) up, they will be gone forever.
We need to have a strong sense of 5 (responsible) and it’s high time for us to think about 6 we can help save energy and preserve these fuels.
What about turning off anything 7 (electricity) we are not using? That’s a start! We can also recycle things such as newspapers, cans, bottles, and plastic—including plastic bags. Plastic bags start out as either oil 8 coal, and one big city can use millions of plastic bags in a year. When we use recycled things, it takes less energy 9 making something new.
Cars consume a lot of fuel, but there 10 (be) a variety of measures that car owners can take to preserve fuel. Try asking your family whether we can take a bus or walk instead of using the car.
