( But ( ( ( the weight ) ( of ( an object ) ) ) ( ( can ( ( change , ) ( because ( ( the weight ) ( is ( determined ( by ( ( the force ) ( of gravity ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (CC But) (NP (NP (DT the) (NN weight)) (PP (IN of) (NP (DT an) (NN object)))) (VP (MD can) (VP (VB change) (, ,) (SBAR (IN because) (S (NP (DT the) (NN weight)) (VP (VBZ is) (VP (VBN determined) (PP (IN by) (NP (NP (DT the) (NN force)) (PP (IN of) (NP (NN gravity))))))))))) (. .)))
But the weight of an object can change, because the weight is determined by the force of gravity.
(ROOT (S (NP (NNP Weight)) (VP (VBZ is) (NP (NP (DT the) (NN force)) (PP (IN of) (NP (NN gravity))))) (. .)))