( ( have ( ( only ( short days ) ) ( to ( ( find ( enough food ) ) ( to ( ( keep ( them ( ( warm and ) alive ) ) ) ( through ( the ( long ( , ( cold ( winter nights ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB have) (S (NP (RB only) (JJ short) (NNS days)) (VP (TO to) (VP (VB find) (NP (JJ enough) (NN food)) (S (VP (TO to) (VP (VB keep) (S (NP (PRP them)) (ADJP (JJ warm) (CC and) (JJ alive))) (PP (IN through) (NP (DT the) (JJ long) (, ,) (JJ cold) (NN winter) (NNS nights)))))))))) (. .)))
have only short days to find enough food to keep them warm and alive through the long, cold winter nights.
(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))))))) (. .)))