Michael Alexander K. Halliday (1925)
A British linguist, developed an internationally influential grammar model, the systemic functional grammar (which also goes by the name of systemic functional linguistics [SFL]).
His Systemic-Functional (SF) Grammar is a sociologically oriented functional linguistic approach and one of the most influential linguistic theories in the twentieth century, having great effect on various disciplines related to language, such as language teaching, sociolinguistics, discourse analysis, stylistics, and machine translation.
Systemic-Functional Grammar has two components: systemic grammar and functional grammar.
Systemic grammar : aims to explain the internal relations in language as a system network, or meaning potential
Systemic-Functional Grammar is based on two facts:
language users are actually making choices in a system of systems and trying to realise different semantic functions in social interaction; and
language is inseparable from social activities of man.
Halliday views language development in children as “the mastery of linguistic functions”, and “learning a language is learning how to mean”. So he proposes seven functions in children’s model of language:
Instrumental: This is when the child uses language to express their needs (e.g.'Want juice')
Regulatory: This is where language is used to tell others what to do (e.g. 'Go away')
Interactional: Here language is used to make contact with others and form relationships (e.g. 'Love you, mummy')
Personal: This is the use of language to express feelings, opinions, and individual identity (e.g. 'Me good girl')
The next three functions are heuristic, imaginative, and representational, all helping the child to come to terms with his or her environment.
Heuristic: This is when language is used to gain knowledge about the environment (e.g. 'What the tractor doing?')
Imaginative: Here language is used to tell stories and jokes, and to create an imaginary environment.
Representational: The use of language to convey facts and information.
According to Halliday, the adult’s language becomes much more complex and it has to serve many more functions, and the original functional range of the child’s language is gradually reduced to a set of highly coded and abstract functions.