( So ( ( ( ( gas ( has ( ( ( no ( fixed volume ) ) or ) shape ) ) ) and ) ( it ( conforms ( to ( ( the shape ) ( of ( its container ) ) ) ) ) ) ) . ) )
(ROOT (S (IN So) (S (NP (NN gas)) (VP (VBZ has) (NP (NP (DT no) (VBN fixed) (NN volume)) (CC or) (NP (NN shape))))) (CC and) (S (NP (PRP it)) (ADJP (JJ conforms) (PP (TO to) (NP (NP (DT the) (NN shape)) (PP (IN of) (NP (PRP$ its) (NN container))))))) (. .)))
So gas has no fixed volume or shape and it conforms to the shape of its container.
(ROOT (S (NP (DT A) (NN gas)) (VP (VBZ assumes) (NP (NP (DT the) (NN shape)) (PP (IN of) (NP (PRP$ its) (NN container))))) (. .)))