Whereas the preceding chapters focus on the acquisition side of vocabulary study, the chapters in Part IV concentrate on teaching. Jan H. Hulstijn leads off with a discussion of mnemonic methods. Drawing on the literature and on personal experience as both a teacher and a learner, he argues that keyword mnemonics are a useful supplement to guessing from context. The use of mnemonics accords with generally accepted principles of vocabulary learning and teaching, such as an avoidance of rote learning, an avoidance of context-free learning, and the need for elaboration and rehearsal. Hulstijn argues that a theoretical basis for the approach can be found in the concept of spreading activation, and he notes that we remember concrete words better than abstract ones. The final part of his essay is devoted to practical guidelines for vocabulary learning and teaching, including how to develop metacognitive awareness (cf. Chapters 4–6), how to use nonvisual verbal mediators, how to use mnemonics in language production, and how to use rehearsal techniques.

James Coady next argues that proficient second language users acquire most of their vocabulary knowledge through extensive reading. For beginners, however, this presents a problem: How can they learn words through extensive reading if they don't have enough words to read extensively? Coady proposes that this dilemma can be overcome in two stages. First, learners should be given explicit instruction and practice in the 3,000 most common words in the language, to the point of automaticity (Laufer makes a similar recommendation in Chapter 2).