(S (S (ADVP (RB Later)) (COMMA ,) (S (BASENP (DT the) (NNP UN)) (VP (VP (VBD sent) (BASENP (DT a) (NN patrol))) (S (VP (TO to) (VP (VP (VB pick) (PRT (RP up))) (NP (BASENP (NNS personnel)) (VP (VBN left) (ADVP (RB behind)))))))))) (PERIOD .))