Martin (1992: 40):
It should also be noted in passing that in the model being developed here both grammar and discourse semantics make meaning. Levinson (1983: 290) comments that the first move in the following text is both "a question and an offer, as indicated by the response".Would you like another drink?— Yes, I would, thank-you, but make it a small one.This is just what would have been predicted by the model developed to this point. Grammatically the first move is a demand for information (interrogative) while semantically it offers goods (Offer); both MOOD and SPEECH FUNCTION contribute a layer of meaning to the clause.
 It is true that both grammar and semantics make meaning — making meaning is semogenesis. However, this is quite distinct from the stratification of content plane as meaning (semantics) and wording (lexicogrammar), which construes two levels of symbolic abstraction in an intensive (elaborating) identifying relation.
 Grammatically, the first move is an interrogative, which is a congruent realisation of a demand for information (question) at the level of semantics. However, this interrogative clause realises an offer. Offers are not grammaticised in the mood system and are realised by interrogatives, declaratives or imperatives, depending on the tenor (context) being realised.
 This requires clarification. The mood of a clause, at the level of wording (lexicogrammar), realises speech function, at the level of meaning (semantics). The meaning of a clause consists of the semantic choices that the grammatical choices realise. The clause itself is at the level of wording, not meaning.