cvrkutati

1. (of birds) to chirp; to twitter; to warble
   Ujutru ptice cvrkuću ispod mog prozora. — In the morning birds chirp under my window.
   Čuli smo kako vrapci cvrkuću u parku. — We heard the sparrows twittering in the park.
2. (of people) to chatter; to twitter
   Devojčice su cvrkutale u dvorištu ceo dan. — The little girls chattered away in the yard all day.