Question

He sleeps in sunlight at peace( use the adverb from of peace)

Answer 1

He sleeps in sunlight at peace ----
He sleeps in sunlight peacefully...

Hope it'll help you :)

Answer 2

HEY MATE!

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Question- He sleeps in sunlight at peace( use the adverb form of peace)

Answer-  As the adverb form of peace is peaceful, The right sentence will be:

He sleeps in the sunlight peacefully.

Hope it helps you!