Congruency refers to all the parts of something working together; in ELT this means how different elements work together to produce successful communication. These elements can include such tools as intonation, gesture, grammatical structure and lexis.
Learners working on matching different intonation patterns to utterances are thinking about how different elements of language can work together.
In the classroom
The concept of congruency - all parts working together - is a useful one, as learners and teachers need to consider how a wide variety of language tools combine to make communication effective. One way to draw learner attention to this is to emphasize the impact on the listener or reader of their communication, for example by asking them ‘how would a reader feel?' or ‘how would a listener respond?'