Lets suppose my sister is Ritu
Me - Ritu! can't you shut down all the lights and fans when you leave the room?
Ritu - Calm down no worry
Me - Why should I don't worry?
Ritu - We have enough money so that we can affort this electricity
Me - ( in anger ) What you should think that by closing a single light you are making one more house brightened
Ritu - I got it now I will try to save electricity.
Me - Thanks for understanding it Ritu.