Few Americans had noticed it.
( ( Few Americans ) ( ( had ( noticed it ) ) . ) )
(ROOT (S (NP (JJ Few) (NNPS Americans)) (VP (VBD had) (VP (VBN noticed) (NP (PRP it)))) (. .)))
Americans hardly noticed it.  
( Americans ( hardly ( ( noticed it ) . ) ) )
(ROOT (S (NP (NNPS Americans)) (ADVP (RB hardly)) (VP (VBD noticed) (NP (PRP it))) (. .)))