It is incontrovertible that the knowledge of English grammar is indispensable to attaining real English proficiency. Its study helps learners master the correct use of the language as well as its structures. Without the knowledge of English grammar, users of English might have a hard time communicating intelligibly, accurately, and unambiguously, especially within the formal business and academic environments. This is the main reason why English grammar is taught in schools, colleges, and language institutes. This is also the major reason why many English competence tests and examinations have been put in place to test users' level of proficiency. Consequently, the book, "THE INS AND OUTS OF ENGLISH GRAMMAR 1" has been written to equip learners with all the grammar tools needed to face and surmount any English (grammar) competence test or examination however tough it may be. The book has also been released to help improve learners' language proficiency, by empowering them to speak and write flawless English without any fear of making grammatical mistakes. While it might be impossible to completely demystify English grammar in one book, the book has consequently been written in two parts. This part (Book 1) discusses the English parts of speech and related topics, while the concluding part (Book 2) will treat other important topics in English grammar. Candidates who desire resounding success in any English grammar examination will do well to have a copy of this book for compulsory reading and study.