adjective
He is the only one who can identify the murderer
adverb
He has a face that only a mother could love. They have been here only twice. She gets her own way only because she has a tantrum if anyone crosses her. Harry was correct in one respect only
She is only seventeen. I received your note only today. Don't get excited, it's only a small present
conjunction
The flowers are lovely, only they have no scent
US