(S (S (BASENP (DT The) (NNPS Greens)) (VP (VBD had) (VP (ADVP (RB previously)) (VP (VBN proposed) (SBAR (IN that) (S (BASENP (RB only) (JJ dangerous) (NNS dogs)) (VP (MD should) (VP (VB be) (VP (VBN microchipped)))))))))) (PERIOD .))