(S (S (S (VP (TO To) (VP (VP (VB stop) (BASENP (DT the) (NN fire))) (PP (IN from) (S (VP (VBG spreading) (PP (TO to) (NP (BASENP (JJ other) (JJ nearby) (NNS buildings)) (COMMA ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (VP (ADVP (RB closely)) (VP (VBN grouped) (ADVP (RB together))))))))))))))) (COMMA ,) (S (BASENP (PRP they)) (VP (VBD were) (VP (VBN forced) (S (VP (TO to) (VP (VP (VP (VB pull) (NP (BASENP (DT some)) (PP (IN of) (BASENP (PRP them))))) (PRT (RP down))) (S (VP (VBG using) (NP (BASENP (NN nothing)) (PP (IN but) (BASENP (NN man) (NN power))))))))))))) (PERIOD .))