( This ( ( ( is ( analogous ( to ( ( the addition ) ( of water ) ) ) ) ) ( to ( alkenes ( we ( studied recently ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ is) (ADJP (JJ analogous) (PP (TO to) (NP (NP (DT the) (NN addition)) (PP (IN of) (NP (NN water)))))) (S (VP (TO to) (VP (VB alkenes) (S (NP (PRP we)) (VP (VBN studied) (ADVP (RB recently)))))))) (. .)))
This is analogous to the addition of water to alkenes we studied recently .
(ROOT (S (NP (NNS Alkenes)) (VP (VBP are) (VP (VBN formed) (PP (IN from) (NP (NP (DT an) (NN alcohol)) (SBAR (WHNP (WDT that)) (S (VP (VBZ loses) (NP (NN water))))))))) (. .)))