One obvious conclusion from this research is the complexity of second-language learning; any model has to account not just for grammatical development but also for the contributions made by the learner and by the learner's environment, not to mention the individual differences between learners, and the effects of learning a second language on the learner, a field too vast to include here. If nothing more, we can rule out simple accounts of second-language learning. A further general issue is whether a second language can be learnt in the same way as a first. An adequate discussion of this can only take place if we settle in advance which model of first-language acquisition we are comparing to second-language learning: it is hardly satisfactory to try to prove or disprove the similarity between the processes by choosing select examples from either field . . . Obviously any teaching syllabus or materials will be more effective if they pay attention to what is known about the developmental sequence the learner goes through, the comprehension and production strategies he uses, his attitudes and motivations, the interactions he wants to take part in, and so on. But what can the teacher do who is unable to change the syllabus or course that he uses? Above all, the teacher has to recognise the active contribution made by the learner; regardless of what the teacher wants him to do, the learner adopts certain learning and production strategies; success in learning is a product of many different factors in the learner, most of them out of the teacher's control. In particular, the successful learner wants to communicate actively through the language. The teacher's recognition of the learner's contribution, in particular of the integrative motivation, will lead him not only to stress the ultimate aim of interacting with native speakers but also to encourage the students to interact with each other and with him in meaningful ways in the classroom; this probably means providing a variety of interaction patterns, not just the one in which all communication is channelled through the teacher. The teacher's awareness of the learner's contribution will also make him more conscious of the extent to which he can call upon the maturer cognitive processes of the second-language learner in activities where language is less involved. In terms of teaching techniques, it leads to activities that encourage the students to communicate and interact through the new language about things that vitally concern them, here and now in the classroom, rather than with a native speaker on some far-off occasion in the future; . . . This new emphasis brings us to a point where the goals of language teaching are no longer defined simply by the language syllabus the student is expected to know, or by the usefulness of the language to some conjectured function in the student's later life, but by their contribution to the social and psychological development of the individual; it may restore a central educational role to language teaching in addition to its academic and utilitarian roles.