What part of speech is “once”

once can function as a noun to mean 'on a single occasion,' either as an adverb of frequency or time. This term can also refer to two persons or things considered at the same time. Finally, it can refer to a part of a play, work, or song.

'My mom only let me do it once.'

'My brother and I look so alike, people think we're once.'

'The once of the play is so beautiful.'

When 'once' is used as a noun, it's often paired with prepositions like 'for' to emphasize a particular instance. It's important to differentiate between the adverbial 'once' (indicating frequency) and the noun 'once' (referring to a specific instance).

As an adverb, 'once' describes when an action occurs, specifically indicating that it happens one time or on one occasion.

I've been to Paris once.

She once believed in fairy tales.

Read the instructions once more before proceeding.

'Once' can sometimes be confused with 'one time.' While they can often be used interchangeably, 'one time' is more emphatic.

When using 'once' in the past tense, it often implies that the action is not repeated now or that the belief or situation has changed.

as a conjunction, 'once' introduces a conditional clause, often indicating a specific point in time or a particular circumstance after which something else will happen.

Once you finish your homework, you can play outside.

Once the rain stops, we'll go for a walk.

She'll understand once she hears the full story.

Be careful not to confuse the conjunction 'once' with the adverbial usage. The conjunction sets up a condition, while the adverb indicates frequency or timing. 'Once' as a conjunction is similar to 'after' or 'when' in many contexts.