Infinitive Pronouns

Indefinite pronouns refer to unspecific items that act like a noun.

(?) Do you want anything?
(?) Do you want something?
(+) I want something to eat.
(--) I don’t want anything to drink.
(--) I have nothing to drink.

(?) Did you go anywhere?
(?) Did you go somewhere?
(+) I want to go somewhere.
(--) I don’t want to go anywhere.
(--) We went nowhere.

(?) Do you know anyone?
(?) Do you know someone?
(+) I know someone like that.
(--) I don’t know anyone here.
(--) I know no one here.

(?) Do you know anybody?
(?) Do you know somebody?
(+) I know somebody like that.
(--) I don’t know anybody here.
(--) I know nobody here.

Note: The words anytime, sometime, and sometimes (for when) and anyhow and somehow (for how) are used like adverbs, not like pronouns.