Imagine you are playing outside and suddenly you see smoke coming from a building. That's when people call the fire brigade, which is a special team of firefighters who help put out fires and keep everyone safe.
When they receive a call, they quickly get into their big red fire trucks, which have loud sirens and flashing lights. This helps get them to the emergency quickly.
Once they arrive at the scene, the firefighters jump out and get to work. They use big hoses to spray water on the fire, and they wear special gear to keep themselves safe from the heat and smoke. Their main goal is to make sure everyone is safe and to stop the fire from spreading.
So, when someone says 'fire brigade on a call,' it means they are rushing to help someone who needs them during a fire or other emergency!