The book "Head-driven Phrase Structure Grammar" by Carl Pollard and Ivan Sag is a major contribution to the field of linguistics and computational linguistics. It presents a comprehensive overview of Head-driven Phrase Structure Grammar (HPSG), a grammatical framework that has become a standard in category-based syntax. The book is well-structured and provides a detailed analysis of various syntactic phenomena, including agreement, subcategorization, unbounded dependencies, control, binding theory, and quantification. It also compares HPSG with other grammatical theories, such as Principles and Parameters, and provides a clear cross-theoretical discussion of major syntactic issues. The book is essential for anyone interested in building an NLP system with a nontrivial syntactic component. It is also highly recommended for readers interested in either HPSG or German syntax, as it presents current research and includes several technical and theoretical innovations. However, the book is editorially poor, with typos and incorrect referencing of examples. The book covers a wide range of topics, including the theory of agreement, anaphoric binding, control phenomena, and unbounded dependencies. It provides a detailed analysis of these topics and discusses the theoretical value of integrating various kinds of information in each constituent or sign. The book also discusses the interaction between syntactic and semantic constraints, and the role of lexical rules in HPSG. The book is well-structured and provides a detailed analysis of various syntactic phenomena. It is a comprehensive overview of HPSG and is essential for anyone interested in the field of linguistics and computational linguistics. The book is highly recommended for its detailed analysis and comprehensive coverage of the topic.The book "Head-driven Phrase Structure Grammar" by Carl Pollard and Ivan Sag is a major contribution to the field of linguistics and computational linguistics. It presents a comprehensive overview of Head-driven Phrase Structure Grammar (HPSG), a grammatical framework that has become a standard in category-based syntax. The book is well-structured and provides a detailed analysis of various syntactic phenomena, including agreement, subcategorization, unbounded dependencies, control, binding theory, and quantification. It also compares HPSG with other grammatical theories, such as Principles and Parameters, and provides a clear cross-theoretical discussion of major syntactic issues. The book is essential for anyone interested in building an NLP system with a nontrivial syntactic component. It is also highly recommended for readers interested in either HPSG or German syntax, as it presents current research and includes several technical and theoretical innovations. However, the book is editorially poor, with typos and incorrect referencing of examples. The book covers a wide range of topics, including the theory of agreement, anaphoric binding, control phenomena, and unbounded dependencies. It provides a detailed analysis of these topics and discusses the theoretical value of integrating various kinds of information in each constituent or sign. The book also discusses the interaction between syntactic and semantic constraints, and the role of lexical rules in HPSG. The book is well-structured and provides a detailed analysis of various syntactic phenomena. It is a comprehensive overview of HPSG and is essential for anyone interested in the field of linguistics and computational linguistics. The book is highly recommended for its detailed analysis and comprehensive coverage of the topic.