Child Language: Acquisition and Development (2 ^nd Edition) is a textbook on first language acquisition. Centering on the nature-nurture debate, this book introduces fundamental principles and theories of first language acquisition, as well as the recent findings of research conducted on child language by both nativists and non-nativists. The book consists of ten chapters that discuss basic issues of child language acquisition and development. Each chapter is presented with a wealth of research that has been conducted in this domain, accompanied by explanations of the linguistic terms and concepts involved. The book begins with an introduction of studies on language acquisition that have been conducted in different areas of linguistics, such as phonology, vocabulary and lexicon, morphology, and syntax. Subsequent chapters deal with broader themes in language acquisition, such as human language vs. animal communication, critical periods, input and interaction in language acquisition, language perception and production in the first year, as well as vocabulary development and morphological processes. The key chapters present the readers with two different perspectives on the acquisition of syntax: nativist and usage-based approaches. In addition to presenting the “what” and “when” of various aspects of language acquisition and development, the book encourages readers to examine different theories related to “how” and “why” through the arguments and data presented.