Why this should be is a subject of endless debate among linguists, it might be to do with the movement of your tongue or an ancient language of the Caucasus. It doesn’t matter. It’s the law, and, as with the adjectives, you knew it even if you didn’t know you knew it. And the law is so important that you just can’t have a Bad Big Wolf.

Tense situations

It’s astonishing quite how expert you are at the English language. There are so many tenses you can use without even thinking about it, and almost certainly without being able to name them. It depends how you count them, but there are about 20 that you deploy faultlessly. The pluperfect progressive passive for an extended state of action that happened to you prior to another action in the past is, when you put it like that, rather daunting. But then you’d happily say “I realised I’d been being watched” without breaking sweat or blinking. Think how daunting this is for people learning English. The teacher has to explain to them that the English don’t usually use the present tense for things that are happening in the present. “I brush my teeth” doesn’t mean that you’re doing it right now, it just means that you do it regularly. For things that are actually happening right now you use the present progressive “I’m brushing my teeth” (but only if you can speak with your mouth full).