Part of what we do is we discuss how language works. She and I are both of the generation that was not actually taught grammar. I'm fortunate enough to have picked up quite a bit, mostly from having started learning a foreign language at age nine, so my own grammar is pretty good. The problem is that I have a very hard time explaining to other people why I make the editorial corrections that I do. Yesterday, we were discussing the passive voice, and we looked in her textbook, which was written by a very well-meaning lady who really wanted you to know exactly how German grammar works, but who assumes that you know as much about grammar as she does. Which relatively few people under the age of forty do anymore.
We learned that the passive voice requires the use of something called a "participial phrase." I deduced that this probably involved something called a "participle," but the only thing I knew about a "participle" was that you're not supposed to dangle it. One quick trip to Wikipedia later, and we had our working definition of "participle," which was "a verb that has been pressed into service as an adjective or an adverb." And then we were able to complete our discussion of the passive voice, which is beloved by Germans, but which English speakers do not like nearly so much.
Language teaching skillz, I haz them!
*I learned German starting with Asterix. My first German sentence ever was "Die spinnen, die Römer," and you will pry my old, beat-up German-language Asterix paperbacks out of my cold, dead hands.