My fiancee is French and whenever she speaks (an almost perfect) Spanish, I always make the effort to repeat back errors she makes, in the correct form, without interrupting the dialog. On the medium term, that single act works wonders. I suggest that as a subtle alternative to pointing out errors, that can also be handy!

This is a good approach. I even use the same technique with my very young child, who still makes mistakes with English irregular verbs.

I think the perceived separation between subjects is largely artificial. English and math seem pretty separate, until you get into discrete math and algebra and you realise formal systems are just languages with grammars, syntax, etc.

Nearly everything we learn is multidisciplinary. Sometimes it might be an advantage to focus on specific topics in isolation, but it should always be placed in a wider context to properly understand it.

"Wary" stems from the same root as "beware" and "aware". Going back further in time, it can also be connected to "ward", "warden", and "guard".

On the other hand, "weary" stems from "wear", as in "wear and tear", "to wear down", and "this weather has been wearing on me".

you understand what is meant by the mistake in speech, and it goes unmentioned, so something...

*In the medium term...

:)

By the way, your English is far better than my Spanish... ;)