To the sociologists' speculations, add mine.
( ( To ( the ( sociologists ( ' speculations ) ) ) ) ( , ( ( add mine ) . ) ) )
(ROOT (S (PP (TO To) (NP (DT the) (NNP sociologists) ('' ') (NNS speculations))) (, ,) (VP (VB add) (NP (NN mine))) (. .)))
Add my speculation to the sociologists'.
( ( ( Add ( my speculation ) ) ( to ( the ( sociologists ' ) ) ) ) . )
(ROOT (S (VP (VB Add) (NP (PRP$ my) (NN speculation)) (PP (TO to) (NP (DT the) (NNS sociologists) ('' ')))) (. .)))