An author who wanted to develop their narrator as a character might make use a(n) narrative style.

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An author who wanted to develop their narrator as a character might make use a close narrative style.

Narrative is a form of retelling, often in words, something that has occurred.  A narrative techniquerefers to any of several specific methods the author of a narrative uses in order to convey what they wish. To put it simple, a strategy employed in the making of a narrative to relay information to the audience and, particularly, to "develop" the narrative, usuallyto make it more complete, complicated, or interesting.