Bernstein 1975 identifies differences between working class and middle class language that influence achievement
he distinguishes between two types of speech codes
the restricted code
the speech code that is typically used by the working class
has limited vocabulary and is based on the use of short, often unfinished, grammatically simple sentences
speech is unpredictable and may involve only one single word or even a gesture instead
descriptive not analytic
the speaker assumes that the listener shares the same set of experiences
the elaborated code
typically used by the middle class
wider vocabulary and is based no longer, grammatically more complex sentences
speech is more varied and communicates abstract ideas
the elaborated code is context-free
the speaker does not assume that the listener shares the same experiences and so they use language to spell out their meanings explicitly for the listener