( ( ( One gram ) ( of protein ) ) ( ( provides ( four calories ) ) . ) )
(ROOT (S (NP (NP (CD One) (NN gram)) (PP (IN of) (NP (NN protein)))) (VP (VBZ provides) (NP (CD four) (NNS calories))) (. .)))
One gram of protein provides four calories.
(ROOT (S (NP (NP (CD One) (NN gram)) (PP (IN of) (NP (NNS carbohydrates)))) (VP (VBZ provides) (NP (NP (CD four) (NNS calories)) (PP (IN of) (NP (NN energy))))) (. .)))