Conclusion
Beck, McKeown, and Kucan’s (2002) three-tiered vocabulary framework is a valuable tool for teachers’ use in identifying words for explicit instruction in adult ESL classes. By classifying words into the three tiers, teachers can then make informed decisions regarding the type of instruction that is warranted (either brief or elaborated), and select appropriate strategies. The recommendations provided in this article can help teachers streamline their instruction and maximize their impact in the vital area of vocabulary development for adult second language learners.