( Fissioning ( ( takes ( place ( in ( the ( reactor core ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Fissioning)) (VP (VBZ takes) (NP (NP (NN place)) (PP (IN in) (NP (DT the) (NN reactor) (NN core))))) (. .)))
Fissioning takes place in the reactor core.
(ROOT (S (NP (NNP Fission)) (VP (VBZ takes) (NP (NP (NN place)) (SBAR (WHADVP (WRB when)) (S (NP (DT an) (NN animal)) (ADVP (RB simply)) (VP (VBZ divides) (PP (IN into) (NP (CD two) (NNS parts)))))))) (. .)))