Poorly written book, incomprehensible exercises without meaningful content and without definite answers. Most of them, whether auditory or repetitive at the end of each chapter, do not require a correct or wrong answer but rather your opinion and development without substance. So, each grammatical phenomenon you learn in each chapter cannot be practiced since, as I said, the answers concern what each student wants to say and not whether it is correct or wrong. Almost no multiple-choice questions, true or false, fill in the blanks, etc., as would be appropriate based on exams.
The only good thing is that it has good vocabulary and enough texts (which again is negated by the fact that there are no questions about them). It's a shame