usage - Differences between "very" and "very much" as adjective modifiers

The following examples are clearly wrong:

× I am very much tired
× She is very much clever

But the following sounds fine (at least according to OALD):

I am very much afraid that ...
I am very much aware of ...

Worse, the following sounds awkward to me:

× I am very aware of ...

I wonder some sound ok while the others do not. Does it have to do with the type of adjectives being used? Or is there a subtle nuance between "very" and "very much"? Is "very much" the same as "extremely" (I would guess not, at least in the "afraid" example)? When should/can one use "very much", as opposed to "very"? Are there differences between spoken and written uses?

Answer

I'd say "very much" isn't used with adjectives of characteristics/qualities that tend to be inherent or permanent (She's very intelligent.)

And we tend to use very much with other adjectives, especially if they go with a preposition. (I'm very much aware OF the fact that...)

Good question. I can imagine my students asking me this in the near future.