CONCEPTS. The ESL teacher understands fundamental language concepts, and knows the structure and conventions of English language.
The ability speakers have to produce and understand an unlimited number of familiar, unfamiliar and/or novel utterances. The ability speakers have to recognize that certain utterances are not acceptable and simply do not belong to their language.
Knowledge of lexical items and rules of morphology, syntax, semantics and phonology.
The ability the learner has to connect sentences in stretches of discourse and to form meaningful utterances.
The knowledge of socio-cultural rules of language and discourse. An understanding of the social context is required: roles of participants, information they share, and the function of the interaction.