Only after a common convention for bar codes had been established and in use for several years did retailers turn to such systems to transmit and receive data from suppliers.
( Only ( ( after ( ( a ( common convention ) ) ( for bar ) ) ) ( codes ( ( ( ( had ( been established ) ) and ) ( ( in ( use ( for ( several years ) ) ) ) ( ( ( did ( retailers turn ) ) ( to ( such systems ) ) ) ( to ( ( ( ( transmit and ) receive ) data ) ( from suppliers ) ) ) ) ) ) . ) ) ) )
(ROOT (S (RB Only) (PP (IN after) (NP (NP (DT a) (JJ common) (NN convention)) (PP (IN for) (NP (NN bar))))) (NP (NNS codes)) (VP (VP (VBD had) (VP (VBN been) (VP (VBN established)))) (CC and) (VP (PP (IN in) (NP (NP (NN use)) (PP (IN for) (NP (JJ several) (NNS years))))) (VBD did) (NP (NNS retailers) (NN turn)) (PP (TO to) (NP (JJ such) (NNS systems))) (S (VP (TO to) (VP (VB transmit) (CC and) (VB receive) (NP (NNS data)) (PP (IN from) (NP (NNS suppliers)))))))) (. .)))
Retailers only adopted the use of such systems once bar codes had become common practice.
( Retailers ( only ( ( ( adopted ( ( the use ) ( of ( such systems ) ) ) ) ( once ( ( bar codes ) ( had ( become ( common practice ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NNS Retailers)) (ADVP (RB only)) (VP (VBD adopted) (NP (NP (DT the) (NN use)) (PP (IN of) (NP (JJ such) (NNS systems)))) (SBAR (IN once) (S (NP (NN bar) (NNS codes)) (VP (VBD had) (VP (VBN become) (NP (JJ common) (NN practice))))))) (. .)))