His teacher was horrified to hear Little Johnny swearing in school.

'I never want to hear you using language like that again. Where on earth did you pick up such foul-mouthed talk?'

'From my Dad,' said Johnny.

'Well, he should be ashamed of himself,' said the teacher. 'And it's no reason for you to talk like that. Anyway, you don't even know what it means.'

'I do!' said Johnny. 'It means the car won't start.'