( ( ( One gram ) ( of carbohydrate ) ) ( ( contains ( four calories ) ) . ) )
(ROOT (S (NP (NP (CD One) (NN gram)) (PP (IN of) (NP (NN carbohydrate)))) (VP (VBZ contains) (NP (CD four) (NNS calories))) (. .)))
One gram of carbohydrate contains 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))))) (. .)))