( Fermentation ( ( ( is usually ) ( ( ( an ( anaerobic respiration ) ) , ) ( done ( without ( ( the presence ) ( of oxygen ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Fermentation)) (VP (VBZ is) (ADVP (RB usually)) (NP (NP (DT an) (JJ anaerobic) (NN respiration)) (, ,) (VP (VBN done) (PP (IN without) (NP (NP (DT the) (NN presence)) (PP (IN of) (NP (NN oxygen)))))))) (. .)))
Fermentation is usually an anaerobic respiration, done without the presence of oxygen.
(ROOT (S (NP (NNP Fermentation)) (VP (VBZ does) (RB not) (VP (VB use) (NP (NN oxygen)))) (. .)))