Can adverbs act as subject complements?

Question

Example:

He is here.

Or

She is there.

I have been taught that subject complements are adjectives, nouns, pronouns or phrases of them, but in the above example the adverb 'here' is describing the subject in a way that it can't be removed from the sentence (I think).

Are 'here' and 'there' considered adjectives or nouns in these examples?

Can somebody please explain this to me?

Answer 1

He is here.

She is there.

Yes, "here" and "there" are predicative complements, but in accordance with modern grammar they are best classified as locative prepositions. Compare "He is in this place" / She is in that place", where the prepositional meaning is clear.

They are intransitive prepositions, of course, since they are one-word phrases.