摘要：Bilingualism and bilinguality are two concepts of great importance for sociolinguistics and mainly to the theories of language teaching and learning. In spite of their importance (or because of it) there is no agreement concerning their definition. In this paper we propose a definition for them based on issues related to linguistics and educational matters, so that language can benefit from this discussion. We introduce bilingualism as a social situation in which two or more languages are in contact and bilinguality as an individual expression of bilingualism. From this point of view we consider that each individual has a degree of bilinguality which is instable and dynamic according to the situation of bilingualism they are inserted. That means that bilinguality is directly related to the needs imposed by the contexts. Thus, in certain contexts code-mixing is a productive resource to achieve communicative aims; while in other contexts (as when a bilingual is talking to a monolingual) codemixing would not be so relevant. So, we propose that language teaching should take into account such concepts, instead of preventing students from expressing themselves just because they still not know the language they are learning. A bilingual environment in language classes should be observed in order to give way to students’ bilinguality.
