Language Development/Acquisition- What are Halliday's seven functions of a child's language?

Halliday (1978) proposed that there are 7 stages or functions of a child's speech. These are as follows.

Instrumental function - language that is used to fulfil a need, such as to obtain food, drink or comfort. This typically includes concrete nouns.

Regulatory function - language that is used to influence the behaviour of others including persuading, commanding or requesting. 

Interactional function - language that is used to develop relationships and ease interaction. This could include phrases like "I love you mummy" or "Thank you". 

Personal function - language that expresses personal opinions, attitudes and feelings including a speaker's identity. 

Representational/Informative function- language that is used to relay or request information.

Heuristic function - language that is used to explore, learn and discover. This could include questions or a running commentary of a child's actions. 

Imaginative function - the use of language to tell stories and create imaginary constructs. This typically accompanies play or leisure activities.