Rebbi says: "Olelim are infants outside (their mothers' womb), viz. (Jeremiah 9:20) "to cut off the olel outside," and (Eichah 4:4) "Olelim begged for bread. "Yonkim" are those at their mother's breasts, viz.: "and suckers ("yonkei") of the breasts." These and those (at the splitting of the sea) opened their mouths and chanted song before the L–rd.