( ( A ( 4-gram serving ) ) ( ( is ( said ( to ( have ( ( ( ( about ( the ( same sweetness ) ) ) ( as ( ( 8 grams ) ( of sugar ) ) ) ) but ) ( ( only one-fifth ) ( the calories ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (JJ 4-gram) (NN serving)) (VP (VBZ is) (VP (VBN said) (S (VP (TO to) (VP (VB have) (NP (NP (NP (RB about) (DT the) (JJ same) (NN sweetness)) (PP (IN as) (NP (NP (CD 8) (NNS grams)) (PP (IN of) (NP (NN sugar)))))) (CC but) (NP (QP (RB only) (NN one-fifth)) (DT the) (NNS calories)))))))) (. .)))
A 4-gram serving is said to have about the same sweetness as 8 grams of sugar but only one-fifth the calories.
(ROOT (S (NP (NP (CD One) (NN gram)) (PP (IN of) (NP (NN sugar) (CC or) (NN starch)))) (VP (VBZ provides) (NP (NP (CD 4) (NNS calories)) (PP (IN of) (NP (NN energy))))) (. .)))