What part of speech is throughout?

"Throughout" can be either a preposition or an adverb, depending on how it's used in a sentence.

Here are some examples:

Preposition:

* Throughout the day, I felt tired.

* "Throughout the day" modifies the verb "felt," showing the time period during which the action took place.

Adverb:

* We searched throughout the house for the lost keys.

* "Throughout" modifies the verb "searched," indicating the extent or scope of the search.

Let me know if you have a specific sentence in mind, and I can help you determine which part of speech it is in that context.