The book (Durrat Al-Ghawaas fi Awhaam Al Khawaas) written and corrected by Al-Qasim bin Ali Al-Hareeri's (516 A.H.) is regarded one of the most important book which tackles the mistakes in Arabic regarding its syntax, morphology and phonology as well as the connotative mistakes which many people couldn't know their meaning. The study includes many writing mistakes. Also, this book is not very bulky, the matters under correction were (222) ones, particularly, about the people of Baghdad and Basrah as the author lived there.