The book consists of 6 chapters. Chapter One explains the reason why SLA researchers should study the language learning environment in space: population movements associated with internal and external migration and social mobility such as the circuits of commodity production and distribution create much space, in which language learning environment become diverse and uneven. With the spatial perspective, we can fully understand the interactions between language learners and the world or environments.In Chapter Two, by introducing the brief history of Critical (...) Spatial Theory, the author wants to tell us one of the key ideas in the theory: the social production of space, which views space as the product of the social relations of its era. Based on it, the author adds that the production of languages is an integral aspect of the production of space on a global scale. It can help us to understand how social mobility shapes language learning environments. From this perspective, the local environments in which languages are learned are outcomes of the production of space under the influence of mobility. It reiterates the key view that the global mobilities of physical objects (people, goods and information) produce space.In Chapter Three, the author introduces the mainstream views held by modern linguistics: languages are conceptualized as objects in the space. They hold that the spatiality of language is given by providing correct writing systems and standardized rules for various languages. Influenced by mainstream conception of language from modern linguistics, SLA tends to regard languages as self-contained objects in space. However, this view neglects the relation between language and the learning environments. The author holds that the distribution and circulation of languages and their varieties in geographical space produce the spatiality of language, which clears the ground for an environment or object-as-space view of language in Chapter Four.In Chapter Four, the author develops an alternative "objects-as-space" view and introduces three concepts to illustrate spatiality of language: flat ontology, assemblage and mobilities. The concept of flat ontology helps explain what language is and how it comes into being in the world; From assemblage perspective, the author develops the idea that everything is an object, so are human beings and languages. Language (the non-physical object) interacts with various physical objects, forming the language-bearing assemblage. This assemblage is the form of spatiality of language. The mobilities theory explains how language-bearing assemblages develop or change on a global scale because of social mobility, emphasizing the importance of learning environment in SLA. All in all, the author outlines how language makes its way into physical space in the form of assemblages, or assemblages of assemblages.Chapter Five centers on language learning environment. First, the author explains the relation between language learners and their learning environment from an ecological view: the learner is a part of the language learning environment, and second language learning is a spatial interaction between the learners and the semiotic resources provided by environment. Then, the author discusses language environment from two different perspectives. From an 'individual' perspective, environments are assembled by individuals from the spatial resources available; from an 'areal' view, environments are shaped both by local circumstances and global circulations of language-bearing assemblages. Meanwhile, the author also discusses other language environments like the multilingual city and online resources. What the author hopes to develop in this chapter is an environment perspective that grounds the contexts of language learning in space, which helps the readers think about language learning from a spatial perspective.Chapter Six contains three parts. In the first part, it outlines the work of a number of researchers from sociolinguistics and the contribution they made to the spatial theory. In the second part, the author wants to tell us how the idea of language learning environment emerges from his own research. The last part discusses the four main researching routes (areal studies, studies of individuals learning in settings, studies of the construction of individual learning environment and design-based studies) that might influence SLA research on language learning environments and some research methods. The book is in alignment with several recent "turns" occurring in the field of SLA, such as "social turn" (Block, 2003) and "multilingual turn" (May, 2014), both of which bring to the fore the social aspects involved in language learning. While the first "turn" accentuates the role of social context in shaping and influencing learner cognition, the latter highlights how the physical multilingual world remold language learning experiences, and how the mental multilingual world helps raise learners' language awareness, and facilitates their successful construction of an identity of legitimate multi-language users. The book under review joins up the two "turns" in acknowledging that language learners are persons-in-context with organic interaction with social learning environment (Ushioda, 2021). This view has research and pedagogical implications. From the point of doing research, spatial perspectives, advocated in the book, afford huge research potentials for both language teachers and (instructed) SLA researchers to conduct situated investigations, exploring the complex and dynamic nexus between language learners and their surrounding environment (not restricted to people) that play a part in their learning experience, and thus gaining insightful understanding of how individuals and learning contexts are coupled with each other, how they evolve together, and how they constitute an ecosystem that generates affordances, facilitating or constraining language learning. Pedagogically speaking, the spatial perspectives encourage language teachers to hold an ecological view of language teaching and learning, directing their attention to the individuality of each language learner and their complex, dynamic and multifaceted relationality with other learners and the physical realities, rather than solely focusing on the abstract systems (e.g., the development of cognitive aspect). This holistic view allows language teachers to take measures to address concrete questions emerging in and out of the classrooms, and stimulates them to design and experiment with pedagogical interventions that help to create a favorable environment for language learning. This view also invites language teachers to take learner agency into account (Xu & Long, 2020) and to design pedagogical activities that enable learners to take agentive actions to adapt their environments as they actively create and seek their own language learning opportunities, making the world their own (Bronfenbrenner, 1979). In turn, teachers' agency-enabling activities will ultimately help learners to autonomously access a range of resources in this new affordance-rich era to improve their language skills, and thus become more independent in their pathway to life-long learning.Beside the above benefits, the book is also theoretically and methodologically friendly. In illustrating the role of space in SLA, the author invokes a plethora of theories from such disciplines as sociology, sociolinguistics, psychology, etc. This orientation helps readers to build a transdisciplinary framework to capture the multi-layered nature of SLA, and to acquire a nuanced understanding of how language learning is influenced by multiple scales of environmental factors. Methodologically, the author proposes several specific methods that are especially apt to investigate language learning environment. These methods, together with the theoretical foundation laid by the book, will definitely help researchers and language teaching practitioners to further delve into the complex interplay between context and language learners.Admittedly, the book is not without weaknesses. It spends most of its words on illustrating the importance of physical environment in SLA. Another essential component, the virtual environment is insufficiently referenced and discussed. This lacking is undoubtedly a regret the book leaves with us, especially in these years of pandemic, where language learning in virtual spaces is becoming a norm.All in all, the book is an invaluable contribution to the field of SLA, and is worthy of recommending to language teaching practitioners, researchers, and postgraduates in applied linguistics. (shrink)