( ( Going downhill ) ( , ( ( straight downhill ) ( , ( ( with gravity ) ( , ( putts ( ( tend ( to ( roll straighter ) ) ) . ) ) ) ) ) ) ) )
(ROOT (S (S (VP (VBG Going) (ADVP (RB downhill)))) (, ,) (NP (JJ straight) (NNS downhill)) (, ,) (PP (IN with) (NP (NN gravity))) (, ,) (NP (NNS putts)) (VP (VBP tend) (S (VP (TO to) (VP (VB roll) (ADVP (RBR straighter)))))) (. .)))
Going downhill, straight downhill, with gravity, putts tend to roll straighter.
(ROOT (S (NP (NNP Gravity)) (VP (VBZ causes) (S (NP (NNS rocks)) (VP (TO to) (VP (VB roll) (ADVP (RB downhill)))))) (. .)))