The other day, Grandson took a toy that his sister was holding out and gave her a different one. Then he said to her, "This is a quid pro quo."
Daughter 1, startled, said to him, "Do you know what that means?"
And he said, "Yes, it's when someone gives something to you and you find something for them."
I recount this not to suggest that he's a genius but partly because it made us laugh and partly to marvel at the way children - all children - learn language. None of us can remember using this phrase in his presence, but someone must have, and he remembered it just like any other phrase that comes his way. Children have this amazing capacity to learn words, whether it be a little snatch of Latin or a bit of equally difficult English: it's all language to them.
I often thought, when teaching, how impressive it was that even students with moderate learning difficulties could chat away to each other with fluency - and yet it's so difficult to learn a foreign language when you're older and have only an hour or two a week to spend on it. Sit on a bus and listen to a language with which you're unfamiliar - Finnish or Mandarin - and you can't even make out where one word ends and the next begins. And yet, within a couple of years, children are saying everything they need to.
Son visited today. Granddaughter wouldn't come to him for a cuddle at first. "Who is this bearded stranger?" she enquired. Well, she didn't. But you could see her thinking it.
We had just had a plumber to the house, who, in the manner of all plumbers, disapproved of the way the previous chap had tried to fix the blockage in the pipe to a bedroom radiator. Son listened to our tale of their conflicting diagnoses and remedies and nodded. "Much like GPs," he said.