Highlight the coordinating conjunction ("FANBOYS") in the sentence.
Creed Bratton lent me his sweater, so I washed it before giving it back.

Creed Bratton lent me his sweater, SO I washed it before giving it back.

Explanation:

Coordinating Conjuctions:

For

And

Nor

But

Or

Yet

SO

not concrete, existing in thought or as an idea but not having a physical or concrete existence

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