( ( The ( three ( letter codes ) ) ) ( ( are ( code ( meaning ( com Commercial ) ) ) ) . ) )
(ROOT (S (NP (DT The) (CD three) (NN letter) (NNS codes)) (VP (VBP are) (NP (NP (NN code)) (VP (VBG meaning) (NP (NN com) (NN Commercial))))) (. .)))
The three letter codes are code meaning com Commercial.
(ROOT (S (NP (DT The) (JJ genetic) (NN code)) (VP (VBZ works) (PP (IN in) (NP (NP (NN series)) (PP (IN of) (NP (JJ three-letter) (NNS codes)))))) (. .)))