go to sleep vs turn in

go to sleep and turn in both are verbs.

Word	Noun	Adjective	Verb	Adverb
go to sleep	No	No	Yes	No
turn in	No	No	Yes	No

As verbs, go to sleep and turn in are synonyms defined as:

Other synonyms of go to sleep include bed, crawl in, go to bed, hit the hay, hit the sack, kip down, retire, sack out.

go to sleep (verb)	turn in (verb)
prepare for sleep	prepare for sleep
	carry out (performances)
	make an entrance by turning from a road
	to surrender someone or something to another