Abstract
This study investigates the surface forms which mothers use to direct their children's behaviour. It is generally supposed that social factors control a speaker's choice of directive form. However, it is shown that mothers' use of the various forms may be related to a cognitive variable, viz. the degree to which the forms possess the surface properties and, hence, clarity of canonical imperatives. As children get older, mothers' directives lose, in a meaningful order, properties which help to specify their mood and content. It is suggested that the social properties of the context do eventually replace the cognitive demands of the various forms as the primary influence on mother's choices.