( ( Unless ( there ( is ( ( a ( continuous ( , ( unbroken loop ) ) ) ) ( of ( ( conductive material ) ( for ( electrons ( to ( flow through ) ) ) ) ) ) ) ) ) ) ( , ( ( a ( sustained flow ) ) ( simply ( ( ( can not ) ( be maintained ) ) . ) ) ) ) )
(ROOT (S (SBAR (IN Unless) (S (NP (EX there)) (VP (VBZ is) (NP (NP (DT a) (JJ continuous) (, ,) (JJ unbroken) (NN loop)) (PP (IN of) (NP (NP (JJ conductive) (NN material)) (PP (IN for) (NP (NNS electrons) (S (VP (TO to) (VP (VB flow) (PRT (RP through))))))))))))) (, ,) (NP (DT a) (JJ sustained) (NN flow)) (ADVP (RB simply)) (VP (MD can) (RB not) (VP (VB be) (VP (VBN maintained)))) (. .)))
Unless there is a continuous, unbroken loop of conductive material for electrons to flow through, a sustained flow simply cannot be maintained.
(ROOT (S (SBAR (IN Because) (S (NP (NNS charges)) (VP (MD must) (VP (VB have) (NP (DT an) (JJ unbroken) (NN path) (S (VP (TO to) (VP (VB follow))))))))) (, ,) (NP (JJ electric) (NN current)) (VP (MD can) (RB not) (VP (VB flow) (PP (IN through) (NP (DT a) (NN material))) (SBAR (IN unless) (S (NP (PRP it)) (VP (VBZ forms) (NP (DT a) (VBN closed) (NN loop))))))) (. .)))