This chapter defines heritage languages and motivates their study to understand linguistic diversity, language acquisition and variationist sociolinguistics. It outlines the goals of Heritage Language Variation and Change in Toronto (HLVC), the first project investigating variation in many heritage languages, unifying methods to describe the languages and push variationist sociolinguistic research beyond its monolingually oriented core and majority-language focus. It shows how this promotes heritage language vitality through research, training, and dissemination. It lays out overarching research questions that motivate the project:

• Do variation and change operate the same way in heritage and majority languages?

• How do we distinguish contact-induced variation, identity-related variation, and internal change?

• Do heritage varieties continue to evolve? Do they evolve in parallel with their homeland variety?

• When does a heritage variety acquire its own name?

• What features and structures are malleable?

• How consistent are patterns across languages?

• Are some speakers more innovative?

• Can attitudes affect ethnolinguistic vitality?

• How can we compare language usage rates among communities and among speakers?

Chapter 2 focuses on how and why target language input is important for language learners. Authors discuss several different types of input and how it has been found to contribute to second language development. Research-backed approaches for integrating more target language into classrooms of all languages, levels, and ages are presented for teachers to implement in their lessons.

Chapter 1 provides an overview of the major topics in linguistics and second language acquisition (SLA) that are particularly relevant for research with second language learners. The first half of Chapter 1 sets out the foundational concepts, and defines such major terms as linguistics, second language acquisition, and heritage speakers. The chapter addresses such influences on language acquisition as age of acquisition and input quantity and quality, comparing and contrasting different types of learner population (monolingual vs. bilingual, first language vs. second language learners vs. heritage speakers). The chapter provides a brief introduction to generative linguistics and generative SLA, discussing evidence for the biological foundations of language and for Universal Grammar. In the second half of Chapter 1, the discussion moves on to the implicit vs. explicit distinction, which is manifested in second language learning, knowledge, and instruction, and which is relevant both to the nature of teaching interventions and to the measurement of learners’ resulting knowledge.

The Cambridge Handbook of Childhood Multilingualism provides a state-of-the art view of the intra- and interdisciplinarity in linguistics, psychology, sociology, and education through a kaleidoscope of languages, countries, scholars, and cultures. The volume provides: (1) understanding that for most children multilingualism is the linguistic reality in which they grow; (2) an analysis of the effect of languages flowing from different sources, at different times and in different forms, on the uniqueness of child multilingualism processing beyond mono/bilingualism; (3) insights into diversity in the socialization of multilingual children; (4) elaboration of the triangulation of childhood, parenthood, and schooling as natural multilingualism-cultivating conditions motivated by internal and external forces; (5) an integrative approach to multilingual children’s development where the child at the center is cradled by multilingualism and languages, and (6) a focus on multilingualism as a capacity independent from mono/bilingualism. The different language typologies, in different countries and different continents, gathered in this volume tease out what is universal to childhood multilingualism as an agent of “new linguistic realities.”

This chapter takes a critical approach to what we know about the role of the input in multilingual development in early childhood. We include a historical background on competing theoretical approaches to language acquisition in which we argue that usage-based approaches gained traction through the attention paid to input in multilingual acquisition studies. However, in reviewing such studies we draw attention to the limitations of their focus on parental rather than community input. We also draw attention to the need to go beyond the binary distinction of simultaneous and successive acquisition and take into account more fully the child’s age of acquisition in relation to the development of specific areas of language. We review the findings on the link between code-switching or mixing in the input and child productions, pointing out the range of different methodological approaches in identifying mixing. We advocate a more child-centred approach in which the morphosyntactic frame of the child’s utterance is taken into account, and illustrate this with our own study. Finally we argue that future studies should include full ethnographic information about the community setting in which multilingual acquisition takes place.

The conclusion ties together the main themes that have been introduced and explored in the book. Through the adolescent language learning stories of the three authors, the reader is encouraged to make links between theory and/or principles of instructed language learning and practice/experience. The source of the main research evidence and literature which underpinned and informed the writing of the book is presented. The chapter describes a number of teaching scenarios and explains the teaching practice that might have accompanied each scenario, first in the conventional and then in the more progressive language classroom. In each case, the more progressive classroom showcases an example of actual practice. Task-based language teaching is described as one approach that allows for the implementation of principles of effective instructed language learning in the classroom. The chapter concludes by stressing the importance of the classroom learning environment.

Chapter 6 outlines some specialised language planning and course design proposals involving genre-based approaches to Languages for Academic Purposes (LAP) instruction and/or communication training. Essentially, this chapter sketches out some aspects that instruction should take on board, placing the focus on the language and the rhetoric of traditional genres and on the use of data-driven learning tasks involving multilingual text composing. The chapter includes several tasks involving the text-composing practice of remediated and web-mediated emerging genres, as well as hands-on activities for developing writing skills in ASNSs and social media networking. The chapter also provides some reflective tasks involving both familiarisation and practice with digital resources for multimodal text composing. In closing, the chapter advocates the use of assessment methods and self-assessment reflective tools that can be conceptualised as ‘plurilingual portfolios of genre assemblages’ and ‘portfolios of multiliteracies’. These tools can foster independent, self-directed, lifelong learning and support academics and researchers’ professional development throughout their lifespan.

Chapter 4 outlines key properties of language development and explores the question whether the acquisition of an additional or foreign language is fundamentally different compared to the acquisition of a primary language in infancy. Drawing on key findings from studies of second language acquisition involving a range of language pairs, it is shown that some properties of an additional language are acquired naturally despite apparent difficulties caused by input and transfer from previous language knowledge. However, some properties of grammar and language use remain persistently difficult, even despite input and teaching of the properties. We conclude with the claim that the knowledge of Virtual Grammar and its grammatical concepts provides a way for teachers to understand the learnability issues faced by their language learners so that they can then make use of appropriate approaches to address these issues.

Chapter 3 explains the blending process – a thoughtful combination of F2 F and online component. This chapter delineates what the process entails and describes the BLL path. Readers will understand the crucial aspects of the pedagogical plan at the base of the blending process in order to guide a successful blending process. To this end, the chapter identifies and explains the essential organization of the blended path and differentiates between its two main types: input front-loading and input back-loading.

This chapter describes the types of data that empirical community ecologists typically collect, and how these can be incorporated in the Hierarchical Modelling of Species Communities (HMSC) framework as input. While community ecologists apply theoretical, experimental and observational approaches to studying the processes that structure ecological communities, this chapter (and the entire book) focuses mainly on empirical research based on non-manipulative observational data. Understanding the basic features of the data and how they have been collected will be essential for appropriately setting up the HMSC model and interpreting the results. The chapter describes each type of input HMSC data, namely the community data (i.e. the occurrences or abundances of the species), environmental data, data describing the spatio-temporal context, species trait data and phylogenetic data. Finally, the chapter discusses how to best organise the data, as well as how to solve problems arising from missing data.