★ Close to the outline, with strong guidance: the editor has made a thorough and detailed study of the examination outline, and the test sites and key points in the outline have been fully reflected in this book.

★ Profound analysis and wide coverage: This book deeply explains and analyzes the important contents in the textbook, supplemented by a large number of examples to help candidates understand.

★ The topic is novel and the analysis is detailed: For the syllabus and teaching materials, the editor has carefully compiled a large number of exercises and given detailed analysis, which will enable you to master the important test sites quickly and comprehensively.

★ Answering service, timely and accurate: full-time teachers of online schools provide 24-hour answering service for candidates' questions in the learning process of this book through the website answering board.