( You ( ( need ( to ( know ( what ( osmolality ( you ( want ( in ( the ( fixative solution ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP You)) (VP (VBP need) (S (VP (TO to) (VP (VB know) (SBAR (WHNP (WP what)) (S (ADVP (RB osmolality)) (NP (PRP you)) (VP (VBP want) (PP (IN in) (NP (DT the) (JJ fixative) (NN solution)))))))))) (. .)))
You need to know what osmolality you want in the fixative solution.
(ROOT (S (NP (NNP Osmolality)) (VP (VBZ is) (NP (NP (DT the) (NN ratio)) (PP (IN of) (NP (NP (NNS solutes)) (PP (IN in) (NP (NP (DT a) (NN solution)) (PP (TO to) (NP (NP (DT a) (NN volume)) (PP (IN of) (ADJP (JJ solvent))))))))) (PP (IN in) (NP (DT a) (NN solution))))) (. .)))