( ( Not only ) ( ( ( must ( replication ( begin ( in ( the ( DNA synthesis ) ) ) ) ) ) ( phase ( of ( the ( cell cycle ) ) ) ) ) ( , ( but ( ( origins ( are ( ( replicated ( at ( different times ) ) ) ( within ( this phase ) ) ) ) ) . ) ) ) ) )
(ROOT (S (CONJP (RB Not) (JJ only)) (SINV (VP (MD must) (VP (VB replication) (VP (VB begin) (PP (IN in) (NP (DT the) (NNP DNA) (NN synthesis)))))) (NP (NP (NN phase)) (PP (IN of) (NP (DT the) (NN cell) (NN cycle))))) (, ,) (CC but) (S (NP (NNS origins)) (VP (VBP are) (VP (VBN replicated) (PP (IN at) (NP (JJ different) (NNS times))) (PP (IN within) (NP (DT this) (NN phase)))))) (. .)))
Not only must replication begin in the DNA synthesis phase of the cell cycle, but origins are replicated at different times within this phase.
(ROOT (S (PP (IN During) (NP (NP (DT the) (NN synthesis) (NN phase)) (PP (IN in) (NP (DT the) (NN cell) (NN cycle))))) (, ,) (NP (NN dna) (NN replication)) (VP (VBZ occurs)) (. .)))