It was a simple day, walking across a junction near home, I notice a man and his wife in a people carrier sitting waiting on the corner with their engine running. I passed them a leaflet and asked if he could switch off his engine. He said that he was waiting to pick someone up. He looked at the paper as if he couldn’t read. He gave it to his wife. I thought that would be enough. As I passed in front of him, I noticed his engine was still running: so I made the gesture back to him as if to switch off the ignition with my hand. It dawned on him as his wife realised and the engine stopped.