Last month, Doyun's home used a lot of energy. Mom looked at the bill and said, "We need to save energy." Doyun wanted to help, so he made a plan.
First, Doyun walked around the house. A light was on in an empty room, so he turned it off. "Let's turn off the light when we leave a room," he said.
Next, he saw his sister at the fridge with the door open. "Please close the door fast," he said. "When cold air gets out, the fridge must work hard."
On cold days, Doyun did not turn up the heat. He put on a warm sweater instead. On sunny days, he opened the curtains to let the sun in. He and Dad walked to the market and left the car at home.
A lot of our electricity is made by burning coal and gas. When we save energy, we keep the air clean and help our planet. The next month, the bill was smaller. Mom smiled and gave Doyun a big hug.