Essentials of HSK is a series of exercice books prepared for those who are going to sit on the elementary and intemediate HSK test (from Band 3 to Band 8). It is also one of the most intensive exercice books covering most of the language points with detailed explanations so far. The exercise books comprise of four volumes: Listening, Grammar, Reading and Comprehensive exercises. Each comprises of eight sets of special intensive training testing exercises and two sets of simulated tests with detailed explanations. Detailed explanations feature this book, which include not only explanations of almost every grammar point and difficult language point illustrate with examples but also a comparison of easily confused words and phrases in order to best meet the needs of the testers. Complete coverage of all the language points of the Outline of the HSK Test is another distinguishing feature of the books. To serve the needs of different language levels of testers with different aims, we have listed all the grammar points, words and phrases that are in the Outline of the HSK Test and prepared various exercises for the testers to train themselves.