The theory proposed in this book enables linguists to explain how utterances are formed in individual languages and why languages differ in how they denote events and states that may appear physically identical.
The formation of utterances is guided by the principle of functional transparency, which consists of three components:
1.Transparency of the utterance’s role in discourse,
2.Transparency of the functions selected from the set coded in the grammatical system of the given language,
3.Transparency of the role of each constituent within the utterance.

These principles of transparency are realized through various coding means, including lexical categories, inflectional and derivational morphology, linear orders, prosodic features, adpositions, subordinators, and complementizers.