Informal acquisition of L2 English vocabulary

Introduction Research has confirmed a positive relationship between participation in online out-ofschool activities and language skills in L2 English, such as vocabulary knowledge, reading, listening and writing (e.g., Brevik, 2019; Härmälä et al., 2014; Peters, 2018; Sundqvist, 2019). In Europe,the most active daily Internet users are 16–19-year-olds with a high level of formal education. The rate is particularly high in the Nordic countries, where practically all teenagers have Internet access at home and at school (OECD, 2015). In the Nordic context, out-of-school exposure entails that adolescents may choose their online activities and digital communities freely. The most popular activities are similar across Europe: listening to music with English song lyrics, viewing films and multi-episodic series with or without textual aid, browsing the Internet for fun and reading for information, playing computer games, and social networking (Eurostat, 2015; Statista, 2016). However, the time spent on an activity may differ between age groups, as shown in Peters (2018). English being one of the most widespread languages on the Internet, it is not surprising that adolescents themselves believe that web-based activities help them acquire English vocabulary (e.g., Brevik, 2019; Voulgari & al., 2014). Some learners tend to find learning through exposure so effective that they may lose motivation towards the formal study of English (Sundqvist & Olin-Scheller, 2013). However, incidental word learning may also take place in school as a by-product of information search for digitized school projects (Cabot, 2018; Kumpulainen & Mikkola, 2016).