U.S. officials became aware of these secret discussions, certainly by March.
( ( U.S. officials ) ( ( ( ( ( became aware ) ( of ( these ( secret discussions ) ) ) ) , ) ( certainly ( by March ) ) ) . ) )
(ROOT (S (NP (NNP U.S.) (NNS officials)) (VP (VBD became) (ADJP (JJ aware)) (PP (IN of) (NP (DT these) (JJ secret) (NNS discussions))) (, ,) (ADVP (RB certainly) (PP (IN by) (NP (NNP March))))) (. .)))
The officials acted on the secret discussion information.
( ( The officials ) ( ( acted ( on ( the ( secret ( discussion information ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNS officials)) (VP (VBD acted) (PP (IN on) (NP (DT the) (JJ secret) (NN discussion) (NN information)))) (. .)))