∗ This is a revised version of a paper presented to the Conference of Teachers in Approved Schools on “Language, life and learning”, organised by the Home Office Children's Departmer t Development Group and the Programme in Linguistics and English Teaching (University College London) at Sunningdale, May 1969. I am much indebted to Professor Basil Bernstein for his very helpful comments on the paper, which already owes a lot to the inspiration of his work.