( ( When ( ( the weather ) ( begins ( to ( ( cool off ) ( in ( the fall ) ) ) ) ) ) ) ( , ( ( the birds ) ( ( ( fly south ) ( to ( find ( ( warm ( winter ( ( weather and ) plenty ) ) ) ( of food ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (DT the) (NN weather)) (VP (VBZ begins) (S (VP (TO to) (VP (VB cool) (PRT (RP off)) (PP (IN in) (NP (DT the) (NN fall))))))))) (, ,) (NP (DT the) (NNS birds)) (VP (VBP fly) (ADVP (RB south)) (S (VP (TO to) (VP (VB find) (NP (NP (JJ warm) (NN winter) (NN weather) (CC and) (NN plenty)) (PP (IN of) (NP (NN food)))))))) (. .)))
When the weather begins to cool off in the fall, the birds fly south to find warm winter weather and plenty of food.
(ROOT (S (NP (NP (JJ Many) (NNS species)) (PP (IN of) (NP (NP (NNS birds)) (PP (IN in) (NP (JJ new) (NN england)))))) (VP (VBP fly) (ADVP (RB south) (PP (IN for) (NP (DT the) (NN winter) (NNS months)))) (S (VP (TO to) (VP (VB find) (NP (DT an) (NN environment)) (PP (IN with) (NP (JJR more) (NN food))))))) (. .)))