8Aljaafreh, A. & Lantolf, J. P. Negative feedback as regulation and second language learning in the zone of proximal development[ J ]. The Modern Language Journal, 1994(78 ).
9Buckwaher, P. Repair sequences in Spanish L2 dyadic discourse: A descriptive study [ J]. The Modern Language Journal, 2001 (85): 380-397.
10DiCamilla, F. J. & Anton, M. Private speech: A study of language for thought in the collaborative interaction of language learners[ J]. International Journal of Applied Linguistics, 2004(14) : 36-69.
