Or.

Of critical importance to the survival of a living organism.

Requiring a determined or desperate effort to avoid the consequences of failure.

All or nothing.

Any part of a place; anywhere.

This may be surprising, but it's true.

at random

By any means possible; one way or another.

Regardless of the hardships; no matter what difficulties may arise.

An ordinary, standard kind.

At any time; 24/7

A situation in which something is always either extremely abundant or in extremely short supply.

To make a decision, especially after a period of delay; to either take action now or forgo the opportunity.

One must either try to go all the way or not try at all; a high-risk, high-reward strategy.

Of a car or its engine: to perform either very well or not at all.

The practice of flipping a coin in the air, to choose between two alternatives based on which side lands face up.

No matter what the adverse circumstances.

Inconsistent, unpredictable, erratic; sometimes succeeding and sometimes failing with no apparent pattern.

A pure gamble with highly divergent outcomes.

To accept a situation whether one agrees with it or not.

To understand even minimally.