( ( As ( the ( temperature increases ) ) ) ( , ( ( most materials ) ( ( ( ( expand or ) increase ) ( their volume ) ) . ) ) ) )
(ROOT (S (PP (IN As) (NP (DT the) (NN temperature) (NNS increases))) (, ,) (NP (JJS most) (NNS materials)) (VP (VB expand) (CC or) (VB increase) (NP (PRP$ their) (NN volume))) (. .)))
As the temperature increases, most materials expand or increase their volume.
(ROOT (S (PP (IN As) (NP (NN temperature) (NNS increases))) (, ,) (NP (NN volume)) (VP (VBZ increases)) (. .)))