The sentences book of Alzajaji who died in 337 H. It's one of the valuable classified books which attracted the care and importance of scientists explanations this book is very vast famous because of its neat writing and its better formulation and its easy style and being away of implication introducing reasons and protest that many of grammarians take care of. Many of scientists put explanations and comments on Alrajhi sentences book. He has explanations and comments in almaghrib countries more than one hundred and twenty explanations. Lbn assayed Albatlayousi and lbn Osfour Al-Eshbili are one of the most distinguished scientists who explained this book, so I thought that this study is to make balance and I depended on descriptive and analytic methodology that stands on analyze and description by transferring the speech of Alzajaji and, Albatlayousi and lbn Osfour explanation, therefore, the study was made as "Explanation of sentences book between lbn assayed Albatlayouse who died in (444H). In his book "Alhulal in repairing defect from the sentences book, invest, Saeed Abdulkareem Saudi, and between lbn Osfour in his book "Explanation of Alzajaji sentences book" the great explanation, correction Dr. sahib Abujanah. The study came to identification of Alzajaji and gave a detailed idea about him, then, I touched upon the speaking about the importance of the sentences book and the important explanations done by scientists upon the book. Thereafter, the identification of lbn Assayed Albatalyousi and his book "Alhulal to repair defect " I continued the speaking about lbn Osfour and introducing him and his book "the big explanation of sentences book and its importance". Finally, I made a balance between the two books and showing the methods agreement and difference between them. The study came to a number of results and comments and here are the important of them: The sentences book of Alzajaji got a great care, where are the grammarians had explanations, clarifications and comment until its conditions were more and diverse. Each grammatical scientist had his special personality and different explanation from other grammarians. Ibn Assayed Albatalyousi who lived in the sixth century, both of them explained the sentences book but each one had a different methodology and may agree or differ from the other. Ibn Assyed Albatalyousi explanation distinguishes with clearness in research and carefulness and going to summary, and care about the explained material, whereas, Ibn Osfour took care of good dividing and show during explanation, and he had a clear care of borders and identifications, and his explanation distinguish of easiness and safety, so, it's suitable to students of higher studies and researchers. The study commended of necessary importance of studying old grammar books and studying the done explanations, and make a balance with it. Moreover, showing the methodology of the explainers and faces of agreement and difference between them to rich the libraries with these explanations and a service to Arabic language. Keywords: Book of Sentences, Al-Zajjaj, Al-Batalyus, Ibn Osfour Al-Ishbili, Book of Solutions, Book of Explanation of Sentences.