( ( ( A ( scientific theory ) ) however ) ( , ( ( is ( ( a ( well-substantiated explanation ) ) ( of ( ( some aspect ) ( of ( ( the ( natural world ) ) ( based ( on ( ( a body ) ( of ( facts ( that ( have ( been ( repeatedly ( confirmed ( through ( ( observation and ) experiment ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NP (DT A) (JJ scientific) (NN theory)) (ADVP (RB however))) (, ,) (VP (VBZ is) (NP (NP (DT a) (JJ well-substantiated) (NN explanation)) (PP (IN of) (NP (NP (DT some) (NN aspect)) (PP (IN of) (NP (NP (DT the) (JJ natural) (NN world)) (VP (VBN based) (PP (IN on) (NP (NP (DT a) (NN body)) (PP (IN of) (NP (NP (NNS facts)) (SBAR (WHNP (WDT that)) (S (VP (VBP have) (VP (VBN been) (VP (ADVP (RB repeatedly)) (VBN confirmed) (PP (IN through) (NP (NN observation) (CC and) (NN experiment))))))))))))))))))) (. .)))
A scientific theory however, is a well-substantiated explanation of some aspect of the natural world based on a body of facts that have been repeatedly confirmed through observation and experiment.
(ROOT (S (NP (PDT All) (NP (JJ scientific) (NNS explanations)) (CC and) (NP (NNS interpretations))) (VP (VBN based) (PP (IN on) (NP (NNS facts)))) (. .)))