(S (S (NP (BASENP (JJ Several) (NN power) (NNS boats)) (CC and) (BASENP (DT a) (NN spotter) (NN plane))) (VP (VBD were) (VP (VP (VP (VBG escorting) (BASENP (DT the) (VBG surviving) (NNS whales))) (PP (IN towards) (BASENP (NNP Cape) (NNP Naturalist)))) (COMMA ,) (PP (IN in) (NP (BASENP (DT an) (NN operation)) (VP (VBN expected) (S (VP (TO to) (VP (VB take) (BASENP (JJ several) (NNS hours))))))))))) (PERIOD .))