(intransitive, idiomatic, (with "for")) To be on the alert, to be watchful.

Apples are healthy and stave off illnesses. / Healthy eating prevents illness.

People are similar in character to their friends.

Alternative form of keep one's head above water

(idiomatic) To survive or endure, especially in a situation in which one is struggling to avoid being overwhelmed by adverse financial circumstances.

Alternative form of keep one's head

Alternative form of have one's wits about one

Don't do anything you are paying a more qualified person to do.

To avoid creating any controversy, and thus avoid being a target for anybody's criticism.

Alternative form of keep a civil tongue in one's head