Averbal phrase that functions in a sentence only as an adjective is a(n) what sentence? 1)gerund2)pronoun3)participle4)infi nitive

A verbal phrase that functions in a sentence only as an adjective is a 3. participle. For example: He uses a walking stick. - the word walking is a participle used as an adjective here.
A gerund can only be used as a noun, not adjective, a pronoun is only a pronoun, and an infinitive is not used as an adjective.

It could be 1, 2, or 4, depending on the context.1.) they could have had a fight, and she is too humble to say anything further. she wants robert to say something first.2.) maybe he's staring at a computer playing tetris while she's wearing a *really* tight red dress. just sayin' xd3.) is unlikely given that it's only one sentence worth of context long. 4.) it's possible their relationship is more 'mutual hatred' and they tolerate one another.it could be 1, 2, or 4, as long as you can provide sufficient explanation why. remember this as you write!