(S (S (BASENP (DT Some) (NNS students)) (VP (VBD complained) (SBAR (IN that) (S (BASENP (PRP they)) (VP (VBD had) (VP (VP (VP (VBN received) (BASENP (DT no) (NN warning))) (PP (IN from) (BASENP (DT the) (NN university)))) (PP (IN until) (NP (BASENP (DT an) (NN e-mail) (NN alert)) (VP (VBN sent) (PP (NP (QP (ADVP (RBR more) (IN than)) (NN two)) (NNS hours)) (PP (IN after) (BASENP (DT the) (JJ first) (NN incident))))))))))))) (PERIOD .))