( ( Elderly persons ) ( ( should ( ensure ( that ( there ( ( ( is ( ( adequate protein ) ( in ( their diets ) ) ) ) , ) ( for ( protein ( is ( necessary ( ( ( for ( a ( healthy ( immune system ) ) ) ) and ) ( for ( ( ( repair and ) maintenance ) ( of ( body tissues ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Elderly) (NNS persons)) (VP (MD should) (VP (VB ensure) (SBAR (IN that) (S (NP (EX there)) (VP (VBZ is) (NP (NP (JJ adequate) (NN protein)) (PP (IN in) (NP (PRP$ their) (NNS diets)))) (, ,) (SBAR (IN for) (S (NP (NN protein)) (VP (VBZ is) (ADJP (JJ necessary) (PP (PP (IN for) (NP (DT a) (JJ healthy) (JJ immune) (NN system))) (CC and) (PP (IN for) (NP (NP (NN repair) (CC and) (NN maintenance)) (PP (IN of) (NP (NN body) (NNS tissues))))))))))))))) (. .)))
Elderly persons should ensure that there is adequate protein in their diets, for protein is necessary for a healthy immune system and for repair and maintenance of body tissues.
(ROOT (S (NP (NNP Protein)) (VP (VBZ is) (NP (NP (DT an) (JJ important) (NN part)) (PP (IN of) (NP (DT a) (JJ healthy) (NN diet)))) (SBAR (IN because) (S (NP (PRP it)) (VP (VBZ is) (VP (VBN needed) (S (VP (TO to) (VP (VB repair) (NP (NN tissue)))))))))) (. .)))