One of the responsibilities of language teachers is to instruct their students on the use of the dictionary. Teachers should familiarize their students with the various kinds of dictionaries and their uses. Perhaps most important is encouraging the student to read the preface to the dictionary, which provides a description of the type of vocabulary dealt with and a quantitative judgment on the lexical items chosen for inclusion. Sample qualitative and quantitative statements are provided. Besides being useful for learning definitions, etymology, and grammatical usage of words, the dictionary is valuable as a continuing, self-instructional language tool. (AM)