( Now ( ( ( suppose ( that ( we ( have ( a north ) ) ) ) ) ( ( ( magnetic pole ) and ) ( ( a ( south ( magnetic pole ) ) ) ( placed ( near ( to ( one another ) ) ) ) ) ) ) . ) )
(ROOT (S (ADVP (RB Now)) (VP (VBP suppose) (SBAR (IN that) (S (NP (PRP we)) (VP (VBP have) (NP (DT a) (NN north)))))) (NP (NP (JJ magnetic) (NN pole)) (CC and) (NP (NP (DT a) (JJ south) (JJ magnetic) (NN pole)) (VP (VBN placed) (PP (IN near) (PP (TO to) (NP (CD one) (DT another))))))) (. .)))
Now suppose that we have a north magnetic pole and a south magnetic pole placed near to one another.
(ROOT (S (NP (NP (DT The) (NN earth) (POS 's)) (JJ magnetic) (NNS poles)) (VP (VBP have) (VP (VBN switched) (NP (NNS places)) (ADVP (RB repeatedly)) (PP (IN in) (NP (DT the) (NN past))))) (. .)))