First, we mustnt turnon more lights than we need . Then, we must turn fans off when we leave a room. Next, we must close the fridge or freezer after we have taken something out. We mustn switch off the lights when students are the last to leave the classroom. A◇fter that, we mustnt leave the kettle on unattended. F○i●nally,we must close all the windows when we are using the ai•r conditioner.

　　If everyone can do these,I think we can sa○ve electricity.