one day, 24 hours / the daytime, the period from dawn until dusk / (figuratively) a short period of time / one day, someday, an unspecified day / the first day of the month

(literally) one side / everywhere, all around, the whole area / one viewpoint, one opinion or way of thinking / the front page of a newspaper

for the time being, for the present

successive series of questions and responses

vicissitudes, the way that the world or a person prospers one day and declines the next

dotting the i's and crossing the t's

You should treasure every encounter, for it will never recur.

double negative

heavy machine gun

double standard