( ( all ( pH samples ) ) ( ( should ( have ( ( a ( temperature recording ) ) ( associated ( with them ) ) ) ) ) . ) )
(ROOT (S (NP (DT all) (NN pH) (NNS samples)) (VP (MD should) (VP (VB have) (NP (NP (DT a) (NN temperature) (NN recording)) (VP (VBN associated) (PP (IN with) (NP (PRP them))))))) (. .)))
all pH samples should have a temperature recording associated with them.
(ROOT (S (NP (DT All) (NNS enzymes)) (VP (VBP have) (NP (DT an) (JJ optimal) (NN temperature) (CC and) (NN ph.)))))