( ( Yard trees ) ( ( should ( be ( watered ( during ( drought periods ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Yard) (NNS trees)) (VP (MD should) (VP (VB be) (VP (VBN watered) (PP (IN during) (NP (NN drought) (NNS periods)))))) (. .)))
Yard trees should be watered during drought periods.
(ROOT (S (SBAR (IN Because) (S (NP (NNS trees)) (VP (VBP add) (NP (NN water) (NN vapor)) (PP (TO to) (NP (NN air)))))) (, ,) (S (VP (VBG cutting) (PRT (RP down)) (NP (NNS forests)))) (VP (VBZ leads) (PP (TO to) (NP (NP (JJR longer) (NNS periods)) (PP (IN of) (NP (NN drought)))))) (. .)))