( ( ( nuclear envelope ) ( Sometimes ( called ( the ( nuclear membrane ) ) ) ) ) ( , ( it ( ( ( is actually ) ( ( a ( double membrane ) ) ( that ( encloses ( ( the nucleus ) ( of ( eukaryotic cells ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (S (NP (JJ nuclear) (NN envelope)) (ADVP (RB Sometimes)) (VP (VBD called) (NP (DT the) (JJ nuclear) (NN membrane)))) (, ,) (NP (PRP it)) (VP (VBZ is) (ADVP (RB actually)) (NP (NP (DT a) (JJ double) (NN membrane)) (SBAR (WHNP (WDT that)) (S (VP (VBZ encloses) (NP (NP (DT the) (NN nucleus)) (PP (IN of) (NP (JJ eukaryotic) (NNS cells))))))))) (. .)))
nuclear envelope Sometimes called the nuclear membrane, it is actually a double membrane that encloses the nucleus of eukaryotic cells.
(ROOT (S (NP (NNP Nuclear) (NNP enevelope)) (VP (VBZ is) (NP (NP (DT a) (JJ double) (NN membrane)) (PP (IN of) (NP (NP (DT the) (NN nucleus)) (SBAR (WHNP (WDT that)) (S (VP (VBZ encloses) (NP (DT the) (JJ genetic) (NN material))))))))) (. .)))