“Some theorists have argued that second language learners, like children learning their first language, can learn a great deal of vocabulary with little intentional effort. Stephen Krashen (1989) has asserted that the best source of vocabulary growth is reading for pleasure. There is no doubt that reading is an important potential source of vocabulary development for second language learners as it is for first language learners. However, there are some problems with the notion that vocabulary growth through reading requires little effort. As noted above, it is difficult to infer the meaning of a new word from reading unless one already knows 95 per cent or more of the other words, and learners usually need to have many meaningful encounters with a word before they recognize it in new contexts or produce it in their own speaking and writing. As we saw in Chapter 1, Dee Gardner’s (2004) research demonstrates that certain types of words are rare in narratives. Thus, students who read mainly fiction may have little chance of learning words that are essential for their academic pursuits. Conversely, reading mainly science texts will not provide many opportunities to learn the vocabulary of social interaction.”