( ( These sounds ) ( ( may ( become ( very loud ) ) ) . ) )
(ROOT (S (NP (DT These) (NNS sounds)) (VP (MD may) (VP (VB become) (ADJP (RB very) (JJ loud)))) (. .)))
These sounds may become very loud.
(ROOT (S (S (VP (VBN Amplified))) (, ,) (NP (PRP it)) (VP (VBZ becomes) (SBAR (S (NP (NNP louder)) (VP (VBZ happens) (VP (VB do) (NP (DT the) (NN sound)) (PP (IN during) (NP (DT a) (NN resonance)))))))) (. .)))