Teaching, it turns out, is very difficult. Especially if you’re trying to teach something completely impossible, like talking.

Second languages are hard. When I try to speak French, French people stare at me as if my nose has just turned into a fruit bat. Plenty of people can speak other languages though. It’s do-able.

Imagine, though, if you couldn’t speak any language. If you didn’t even know what language was. Starting to understand random noises as a meaningful language, from nothing, then suddenly start speaking it yourself, would obviously be impossible. No one’s really worked out how kids do it. I’d suggest that they learnt it from TV, except there was a time when TV hadn’t been invented. It boggles the mind how parents coped in those dark days.

The best kid’s TV these days is so well made, so entertaining and so gently informative, that it’s very tempting to just let it do the teaching work for us. But we’re not supposed to. Even if telly would do a better job than we can.

I was quite pleased with myself, then, when I came up with the idea of making my son use actual proper language when he wants the TV on, rather than just running up and shouting “Telly on!” at me.

“Can”, “I”, “Watch”, “Telly”, “Please”, “Daddy?”, he repeats after me. If he doesn’t, no telly. It’s great. Now, just putting the telly on feels like I’ve achieved something educational. And I’m teaching him politeness too. I imagine an Ofsted inspector nodding, impressed.

Next I try to get him to say the words without prompting. I start him off with “Can”, then I nod to encourage him to say the rest. He says “Can” then copies my nodding. We nod at each other. My imaginary Ofsted inspector frowns.

I change tack. I try mouthing each word at him. He mouths the words silently back at me, grinning. We mouth words at each other.

Eventually I give up and just put the telly on.

Good old telly. You take it from here.