Any dollar amount you wish to contribute is fine.
( ( ( Any ( dollar amount ) ) ( you ( wish ( to contribute ) ) ) ) ( ( is fine ) . ) )
(ROOT (S (NP (NP (DT Any) (NN dollar) (NN amount)) (SBAR (S (NP (PRP you)) (VP (VBP wish) (S (VP (TO to) (VP (VB contribute)))))))) (VP (VBZ is) (ADJP (JJ fine))) (. .)))
You do not need to commit to a certain amount of money.
( You ( ( ( do not ) ( need ( to ( commit ( to ( ( a ( certain amount ) ) ( of money ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP You)) (VP (VBP do) (RB not) (VP (VB need) (S (VP (TO to) (VP (VB commit) (PP (TO to) (NP (NP (DT a) (JJ certain) (NN amount)) (PP (IN of) (NP (NN money)))))))))) (. .)))