( This ( ( ( ( ( increases heat ) ( in ( the winter ) ) ) and ) ( ( reduces it ) ( in ( the summer ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VP (VBZ increases) (NP (NN heat)) (PP (IN in) (NP (DT the) (NN winter)))) (CC and) (VP (VBZ reduces) (NP (PRP it)) (PP (IN in) (NP (DT the) (NN summer))))) (. .)))
This increases heat in the winter and reduces it in the summer.
(ROOT (S (NP (NP (DT A) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (NN increase)) (PP (IN in) (NP (NN length)))) (VP (VBZ happens) (PP (TO to) (NP (NN metal) (NN railroad) (NNS tracks))) (PP (IN during) (NP (NP (DT the) (NN heat)) (PP (IN of) (NP (DT a) (NN summer) (NN day)))))) (. .)))