do well to cram earplugs in their ears 
(ROOT (S (VP (VB do) (ADVP (RB well)) (S (VP (TO to) (VP (VB cram) (NP (NNS earplugs)) (PP (IN in) (NP (PRP$ their) (NNS ears)))))))))
(ROOT (S (VP (VB ) (ADVP (RB )) (S (VP (TO ) (VP (VB ) (NP (NNS )) (PP (IN ) (NP (PRP$ ) (NNS )))))))))