( ( A ( carbon atom ) ) ( ( has ( ( four electrons ) ( in ( its ( outermost ( valence shell ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN carbon) (NN atom)) (VP (VBZ has) (NP (NP (CD four) (NNS electrons)) (PP (IN in) (NP (PRP$ its) (JJ outermost) (NN valence) (NN shell))))) (. .)))
A carbon atom has four electrons in its outermost valence shell.
(ROOT (S (NP (NNP Carbon)) (VP (VBZ has) (NP (CD four) (JJ valence) (NNS electrons))) (. .)))