A discussion of the relationships between communication in a foreign language and metalinguistic thought given to that language focuses on formal French language learning by adults in their home countries. Experience with adult language learners suggests a resistance to grammatical explanations but an openness to explanations of meaning. It would seem appropriate, then, to transform the traditional and authoritarian grammatical explanation into an activity involving metalinguistic reflection on the learner's part, assisted by the teacher. The use of language to explain language usage thus strengthens the perceived link between language and meaning. Ways to incorporate the conceptualization of language into classroom communication include: (1) simulation of different forms of communication based on inquiry; (2) exercises in the identification and discrimination of the linguistic forms appropriate to certain kinds of situations; (3) spontaneous explanation of linguistic forms and the rules that govern them; and (4) use of graphic aids to visualization. It is concluded that visual instruction, metalinguistic reflection, discovery of linguistic fact through successive approximations, and conceptualization are complementary and indispensable processes in second language learning. (MSE)