Thematic structure is a term in linguistics

Linguistics

Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....

. When people talk, there are purposes in three separable parts of utterances, the act of speech, the propositional content

Proposition

In logic and philosophy, the term proposition refers to either the "content" or "meaning" of a meaningful declarative sentence or the pattern of symbols, marks, or sounds that make up a meaningful declarative sentence...

 and the thematic structure. Because speaking is cooperative, in order that the speaking can be effective in the conversation

Conversation

Conversation is a form of interactive, spontaneous communication between two or more people who are following rules of etiquette.Conversation analysis is a branch of sociology which studies the structure and organization of human interaction, with a more specific focus on conversational...

, speakers have to pay attention to their listeners’ knowledge, state of mind and level of understanding. Speakers can assume that listeners know or do not know what speakers are talking about.

According to Michael Halliday

Michael Halliday

Michael Alexander Kirkwood Halliday is a British linguist who developed an internationally influential model of language, the systemic functional linguistic model. His grammatical descriptions go by the name of systemic functional grammar .-Biography:Halliday was born and raised in England...

, the speakers’ judgements about the listeners’ current mental states are reflected in what is called the thematic structure used.

Thematic structure has three main functions:

• To convey given information and new information
• To subject and predicate
• To frame and insert