(S (S (BASENP (DT A) (NNP United) (NNPS States) (NNP Apache) (NN assault) (NN helicopter)) (VP (VP (VP (VBD provided) (BASENP (NN assistance))) (PP (TO to) (NP (BASENP (DT the) (NN group)) (COMMA ,) (SBAR (WHNP (WP who)) (S (VP (VBD were) (PP (IN in) (NP (BASENP (NNP Lashkar) (NNP Gah)) (COMMA ,) (BASENP (NNP Helmand)))))))))) (COMMA ,) (S (VP (VBG strafing) (BASENP (DT the) (NN area)))))) (PERIOD .))