(S (S (BASENP (DT The) (JJ 17-year-old)) (VP (VBD was) (VP (ADVP (RB allegedly)) (VP (VBG planning) (S (VP (TO to) (VP (VB aid) (PP (IN in) (NP (BASENP (DT the) (NN attack)) (PP (IN on) (BASENP (DT the) (NN school)))))))))))) (PERIOD .))