( Saliva ( ( protects ( ( both ( ( hard and ) soft ) ) ( oral tissues ) ) ) . ) )
(ROOT (S (NP (NNP Saliva)) (VP (VBZ protects) (NP (ADJP (DT both) (JJ hard) (CC and) (JJ soft)) (JJ oral) (NNS tissues))) (. .)))
Saliva protects both hard and soft oral tissues.
(ROOT (S (NP (NNP Saliva) (NNP secretion)) (VP (VBZ initiates) (NP (NN chemical) (NN digestion)) (PP (IN while) (S (ADVP (RB also)) (VP (VBG protecting) (NP (DT the) (JJ oral) (NN cavity)))))) (. .)))