1 The use of ‘referential’ questions, where the teacher asks the class something (e.g. ‘What did you do at the weekend?‘) to which he or she does not know the answer, and which therefore has a genuine communicative purpose. This is in contrast to typical ‘display’ questions (e.g. comprehension questions on a reading text) to which the teacher already has the answer, and only asks so that the class can display their understanding or knowledge. Insights from analyses of discourse inside and outside the classroom (e.g. Long and Sato 1983) have revealed very marked differences between typical classroom talk and non-classroom talk in this respect.

2 Content feedback by the teacher, where the teacher’s response to student contributions focuses on the content of what the student says-the message-rather than on the form (e.g. the correctness of the grammar or pronunciation).

3 The use of speech modifications, hesitations, and rephrasing in the teacher’s own talk, e.g. when explaining, asking questions, giving instructions, etc.

4 Attempts to negotiate meaning with the students, e.g. through requests for clarification and repetition, and giving opportunities for the students to interrupt the teacher and do the same. I shall refer to the features listed above as List A. Conversely, there are a number of features of teacher talk which would be regarded as non-communicative, in that they do not represent the way language is used in many situations outside the classroom, and which I shall refer to as List
B. Examples of these features are:

1 Exclusive or excessive use of display questions.

2 Form-focused feedback, i.e. feedback by the teacher which only shows interest in the correct formation of the students’ contributions (rather than the content).

3 ‘Echoing’ of students’ responses, when the teacher repeats what a student has just said for the benefit of the whole class (something which rarely happens in social intercourse).
4 Sequences of predictable IRF (initiation-response-feedback) discourse chains (Sinclair and Coulthard 1975) in which the teacher initiates the chain (typically by asking a question), a student responds, and the teacher then gives feedback to the student (e.g. ‘good’) before initiating another chain with another question. The structure of spoken discourse outside the classroom is usually more complex and flexible than this (Hoey 1992).