( ( In ( these cases ) ) ( , ( they ( ( are ( heterogeneous mixtures ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (DT these) (NNS cases))) (, ,) (NP (PRP they)) (VP (VBP are) (NP (JJ heterogeneous) (NNS mixtures))) (. .)))
In these cases, they are heterogeneous mixtures.
(ROOT (S (NP (NNS Heterogeneous)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (DT a) (NN mixture)) (SBAR (WHNP (WDT that)) (S (VP (VBZ varies) (PP (IN in) (NP (PRP$ its) (NN composition)))))))))) (. .)))