(S (S (BASENP (DT The) (NN boulder)) (VP (VP (VBD fell) (PP (IN from) (NP (BASENP (QP (RB about) (NN 15)) (NNS metres)) (PP (IN above) (BASENP (DT the) (NN residence)))))) (CC and) (VP (VP (VBD landed) (PP (IN on) (NP (BASENP (NN top)) (PP (IN of) (BASENP (DT the) (NN house)))))) (COMMA ,) (S (VP (VBG crushing) (BASENP (PRP it))))))) (PERIOD .))