A language function is what a speaker or writer does with language: the communicative purpose behind an utterance. Requesting, apologizing, suggesting, complaining, agreeing, disagreeing, inviting, refusing, giving advice, expressing obligation, narrating, persuading: these are all functions.
The concept was formalised by D.A. Wilkins (1976) in Notional Syllabuses and became the organising principle of Communicative Language Teaching. The insight: learners need language organized by what they want to do, not just by grammatical structure.
Every function is realised through exponents, the specific language forms that perform it. A single function typically has multiple exponents at different levels of formality and directness:
| Function | Informal exponent | Neutral exponent | Formal exponent |
|---|---|---|---|
| Requesting | Can you pass the salt? | Could you pass the salt? | Would you mind passing the salt? |
| Suggesting | Let's go. | Why don't we go? | I'd like to suggest that we go. |
| Disagreeing | No way. | I'm not sure about that. | I'm afraid I have to disagree. |
This mapping between function and form is critical for teaching: learners need to know not just what to say but which version to use when. This is where Register enters; the choice of exponent depends on the relationship between speakers, the setting, and the communicative channel.
Functional language is typically taught through a situational context that makes the communicative need clear. A lesson on "making suggestions" might use a scenario where friends are planning a weekend trip. The MFP framework applies directly: teachers analyse the meaning (the pragmatic purpose), the form (the grammatical pattern of each exponent), and the pronunciation (stress, intonation, as in "Why don't we go?" with falling intonation on a suggestion vs. a genuine question).
Key teaching considerations:
A grammar syllabus organises language by structure (present simple, conditionals, passives). A functional syllabus organises by purpose. In practice, most modern coursebooks blend both: a unit might be organized around a function ("giving advice") but explicitly teach the grammar needed to perform it ("should," "ought to," "If I were you"). The MFP analysis bridges both perspectives.