(S (S (BASENP (NN Country) (NN singer) (NNP Martina) (NNP McBride)) (VP (VBZ has) (VP (VBN invited) (S (BASENP (NNP Avila)) (VP (TO to) (VP (VP (VP (VB join) (BASENP (PRP her))) (PP (IN on) (BASENP (PRPD her) (JJ Canadian) (NN tour)))) (PP (IN in) (BASENP (NN summer) (NN 2007))))))))) (PERIOD .))