This chapter starts by exploring basic questions related to the learning of second language vocabulary such as What is a word? and What does it mean to know a word? It discusses form–meaning mapping as well as a word’s grammatical features and its collocations. The chapter focuses on different types of vocabulary knowledge including receptive knowledge, productive knowledge, breath and depth of knowledge, and knowledge related to multi-word units. The chapter refers to corpora as a way to understand how language functions in the real world. It also discusses different ways of learning new words, that is, incidental and intentional learning. The chapter moves onto issues related to the teaching of vocabulary, starting with explicit instruction involving memorization, and then moving on to more implicit activities (e.g., extensive reading). More specific techniques are reviewed such as glossing, corpus-based instruction, form-focused instruction, and strategy instruction.

Chapter 11: Vocabulary and Reading Comprehension. This chapter highlights the central role that vocabulary knowledge plays in reading comprehension and reading development, for both L1 and L2 learners. The centrality of lexical knowledge for reading is supported now by decades of research across many L1 and L2 settings. In particular, the Lexical Quality Hypothesis, as the central concept of the Reading Systems Framework, is the main support for reading comprehension skills. This central idea applies to both L1 and L2 reading development. A further key idea argues that reading amount is the primary mechanism for the development of lexical quality, and by extension, reading abilities. Learning words in context is a complex notion that is developed in detail. Most important in this regard, is the major impact of incidental word learning from both extensive reading and background knowledge. The chapter closes with implications for instruction.

Chapter 18: Extensive Reading. Extensive reading (ER) is understood here as an extensive amount of reading. It is not specifically tied only to enjoyable reading or easy reading, although both of these sources of reading are important. The fundamental idea is that a large amount of understandable input (i.e., within students’ linguistic competence) via reading will develop students’ language and knowledge resources through incidental implicit learning. The benefits of extensive reading emerge over time and is fundamental for developing advanced reading abilities. A large amount of reading (extensive reading) leads to better vocabulary knowledge, better background knowledge, and better reading comprehension. Research in both L1 and L2 of contexts are reviewed, and the role of extensive reading (L2) or amount of reading (L1) is the key foundation for reading development and advanced reading comprehension. The chapter concludes with implications for instruction.

In the reading section of this chapter, we look at how much vocabulary is needed to gain meaning-focused input through reading material written for native speakers. We then look at what a well-balanced reading program for learners of English as a foreign language should contain to maximise vocabulary growth, stressing the need to use vocabulary graded material, particularly graded readers. Such a course should provide opportunities for extensive reading, a focus on language features through intensive reading, and the development of reading fluency though speed reading. Finally, we look at how learners can be supported to read ungraded texts, using techniques such as narrow reading, pre–teaching, intensive reading, and glossing. In order to gain 98 per cent coverage of unsimplified text, learners need to know most of the high-frequency and mid-frequency words, totalling around 8,000–9,000 word families. In the writing section of this chapter, we look at the effect of vocabulary use on the quality of writing, measuring written productive knowledge of vocabulary and how to improve learners’ vocabulary use in writing.

This chapter covers three situations of vocabulary learning, all of which can occur outside the classroom. The first situation has been called extramural English or extramural learning, and could be called learning through entertainment. It involves largely incidental learning through watching TV or movies, surfing the Internet, online social interaction, playing online games, listening to songs, or reading or listening for pleasure. It can also include social interactions with native speakers. Extramural learning is not a part of a regular English course and is not under the control of a classroom teacher. The second situation is supplementary learning. This involves learning outside the classroom which is related to a course occurring inside the classroom. It is largely directed by the classroom teacher. It may involve extensive reading, extensive listening, interacting with others, and writing, and could also involve the deliberate learning of vocabulary and other language features. The third situation has been called self-directed learning and involves the learner organising their own language course without the help of a teacher.

Chapter 6 discusses how vocabulary can be learned incidentally from exposure. This includes incidental learning from reading, listening, television and movies, and other extramural exposure, such as the internet and gaming. It also looks at child L1 vocabulary acquisition.