Mainstream ESL pedagogy has been dominated by monolingual methods for the past century, but the default teaching mode in many EFL contexts is in fact bilingual. A challenge we currently face is to find fresh ways of describing such bilingual teaching. This paper attempts to begin to do so by taking the notions of scaffolding and intertextuality--both deriving from monolingual, monocultural contexts--and applying these to Thai university English classes. Episodes of teacher talk from four classes are examined. It is found that the scaffolding metaphor can readily be applied to bilingual episodes; and that an intertextual analysis across two languages/cultures provides a rich picture of the semiotic restructuring which is enabled by second language development. (Contains 2 figures and 7 tables.)