A young class were enjoying the first day of first grade. The teacher said: "Now that we're all grown up, we aren't going to use baby talk any more. Instead we're going to use grown-up words. Now who would like to start by telling us about what they did in summer vacation?" A little girl called Jenny put up her hand and said: "This summer vacation I rode a choo-choo." "No, Jenny," interrupted the teacher. "We don't say 'choo-choo' any more. We say 'train'. Remember to use grown-up words. Now, wh…