[...] This book will make you work more creatively and effectively with the new, valuable books of the Language of the 4th grade of primary school. It will help you learn not only the use of the language but also its structure. In its pages you will find:
- the answers to all the exercises of the student's book and the workbook
- the unknown words of each text and a few words about its content
- spelling exercises for each lesson, taking into account the most important words of the vocabulary of each unit
- review lessons for each unit with exercises of varying difficulty, so that students of all learning levels can respond to them
- definitions and examples for all the grammatical phenomena encountered by the student and the teacher in the curriculum of the 4th grade
- exercises for written and oral production [...]

(from the authors' preface)