Introduction

To know a language you must know not only its individual words, but also how they fit together. Part of this knowledge entails developing suitable rules to generate all the possible grammatical utterances of the language, but another crucial aspect is coming to know which of the feasible grammatical utterances are idiomatic and nativelike. Pawley and Syder (1983) point out that one of the most difficult tasks for even the most proficient non-native speaker is learning to select that subset of utterances that are customarily used by native speakers, from out of the much greater inventory of those that could be. The choices that result in such ‘customary’ turns of phrase as I'll be back in a tick/mo in preference to I'll return in a short while and let me have a go rather than I should like to try are, because the choices lie entirely within the grammatically possible, subtle to the point of slipperiness, and a non-native can only learn to prefer those which are the usual forms in a given speech community by observation and imitation (see, for example, Willis 1990:63–64). For some idiomatic expressions, the whole is not even a literal reflection of the meanings of the constituent words, and the functional associations can be quite arbitrary. For example, in some varieties of English, nice to meet you is both a greeting and a closer, while nice meeting you is only a closer (Schmidt 1983:152).