Earlier quoted context omitted.
I would imagine the answer would be; the same way you would talk about the concepts out loud to someone else.
So how do you think about something that you can't describe to someone else? There are many things I can deeply understand, but turning that understanding into natural language takes considerable effort. Are people with internal monologues incapable of understanding things they can't verbalize? Or is it that their brain just instantly verbalizes thoughts after the thoughts have already been formed? The latter seems a…
Let me ask you this though: how do you know you understand it? If you've never rendered your idea into language, or seen/heard it put that way, then it has never been criticized or vetted by anyone else.