(S (S (BASENP (NN Ambulance) (NNS crews)) (VP (VP (VBD spent) (BASENP (DT the) (NN night))) (S (VP (VBG rescuing) (NP (BASENP (VBN stranded) (NNS residents)) (VP (VP (VBN caught) (PP (IN off) (BASENP (NN guard)))) (PP (IN by) (BASENP (DT the) (JJ sudden) (NN deluge))))))))) (PERIOD .))