Although we associate trench warfare with World War I, trenches were characteristic also of the Civil War.
( ( Although ( we ( ( associate ( trench warfare ) ) ( with ( World ( War I ) ) ) ) ) ) ( , ( trenches ( ( ( were characteristic ) ( also ( of ( the ( Civil War ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN Although) (S (NP (PRP we)) (VP (VBP associate) (NP (NN trench) (NN warfare)) (PP (IN with) (NP (NNP World) (NNP War) (PRP I)))))) (, ,) (NP (NNS trenches)) (VP (VBD were) (ADJP (JJ characteristic)) (PP (ADVP (RB also)) (IN of) (NP (DT the) (NNP Civil) (NNP War)))) (. .)))
Trenches happened in the Civil War, not just World War I.
( Trenches ( happened ( in ( ( ( ( ( the ( Civil War ) ) , ) not ) just ) ( World ( War I. ) ) ) ) ) )
(ROOT (S (NP (NNS Trenches)) (VP (VBD happened) (PP (IN in) (NP (NP (DT the) (JJ Civil) (NN War)) (, ,) (RB not) (RB just) (NP (NNP World) (NNP War) (NNP I.)))))))