(S (S (S (NP (QP (ADVP (IN At) (JJS least)) (NN 2)) (NNS soldiers)) (VP (VBD were) (PP (IN on) (PP (NN board) (BASENP (DT the) (NN aircraft)))))) (CONJP (COMMA ,) (CC but)) (S (BASENP (PRPD their) (NN condition)) (VP (VP (VBZ is) (RB not)) (VP (VBN known))))) (PERIOD .))