(S (S (S (BASENP (DT Some)) (VP (VBD were) (ADJP (RB still) (JJ alive)))) (CC and) (S (S (BASENP (NN one) (NN marine)) (VP (VBD thought) (SBAR (S (NP (BASENP (DT a) (NN man)) (VP (VBG lying) (PP (IN on) (BASENP (DT the) (NN ground))))) (VP (VBD was) (BASENP (DT a) (NN threat))))))) (SBAR (IN because) (S (S (NP (BASENP (NN one)) (PP (IN of) (BASENP (PRPD his) (NNS arms)))) (VP (VP (VBD was) (RB not)) (ADJP (RB clearly) (JJ visible)))) (COMMA ,) (SBAR (IN so) (S (BASENP (PRP he)) (VP (MD could) (VP (VB be) (VP (VBG hiding) (BASENP (DT a) (NN weapon))))))))))) (PERIOD .))