( ( An orbital ) ( ( is ( ( ( the region ) ( of space ) ) ( where ( ( an electron ) ( is ( likely ( to ( be found ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT An) (NN orbital)) (VP (VBZ is) (NP (NP (DT the) (NN region)) (PP (IN of) (NP (NN space))) (SBAR (WHADVP (WRB where)) (S (NP (DT an) (NN electron)) (VP (VBZ is) (ADJP (JJ likely) (S (VP (TO to) (VP (VB be) (VP (VBN found))))))))))) (. .)))
An orbital is the region of space where an electron is likely to be found.
(ROOT (S (NP (DT The) (NN orbital)) (VP (VBZ is) (NP (NP (DT the) (NN area)) (SBAR (WHADVP (WRB where)) (S (NP (DT an) (NN electron)) (VP (VBZ is) (ADJP (RBS most) (JJ likely) (S (VP (TO to) (VP (VB be) (VP (VBN found))))))))))) (. .)))