The book "International Auxiliary Language Esperanto: Grammar and Commentary" by author George Cox is an essential reference for anyone interested in the Esperanto language. This book provides a detailed overview of the grammar of the language, which was created to promote international communication and understanding. The author draws attention to key aspects of Esperanto grammar and explains their functioning through examples and comments. The book also contains useful tips on using the language in practical situations, as well as recommendations for learning it. "International Auxiliary Language Esperanto: Grammar and Commentary" is an indispensable source of information for anyone who wishes to deepen their understanding of this unique and interesting language.