It soon became clear, however, that language functions alone were not a satisfactory organising principle. In the first place some realisations of functions are in fact little more than fixed phrases (e.g. ‘You must be joking!’ ‘Come off it!’). It may be important to learn them, but that is all you learn! In other words, some functional exponents are just single items — you cannot use them to generate more language as you can with grammatical structure (see 2.2). Another problem lies in how to grade functions. Which should come first? What order should the grammar be taught in for students to be able to apply it to functions? A purely functional organisation meant that notions of difficulty which had informed earlier grammatical syllabuses could not be used since the grammarused to perform one function might be more or less difficult than the grammar used to perform the other. And the teaching of functions raised many problems that grammatical teaching had not previously done.7 (One contentious argument was that by teaching people how British people apologise, for example, you were imposing a cultural stereotype on them.8)