If an author is writing the life story of abraham lincoln but it starts it with the moment lincoln is giving his famous speech the gettysburg address which narrative technique is the author using?

In medias res.

Explanation:

Starting any narrative in the middle is termed as "in medias res" in literary terms. This form of narrative techniques employs the pattern of starting the story or narration from the middle, then moving in between the past or the present or even the future. This enables the narration to make use of the other times or situations whenever it is required.

If an author starts his writing of the life of Abraham Lincoln from the Gettysburg Speech, he is employing this techniques. And by so doing, he can refer or go back to the early life of Lincoln to show his eventual development.

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