This book contains as many as 1,650 core TOEFL iBT/ TOEIC words along with synonyms, definitions, example sentences, and 29 different reviews provided by my colleagues and students. In order to help students preparing for the TOEFL iBT/ TOEIC to memorize the words more effectively, certain words have stars (*), which indicate the degrees of diffculty of memorizing them. Based on my long-term TOEFL/ TOEIC teaching experience, students preparing for the TOEFL iBT/ TOEIC must precisely learn the definitions of the core TOEFL iBT/ TOEIC words in this book to enhance their TOEFL iBT/ TOEIC scores. Once students have memorized all the words, they will be able to start dealing with questions from the reading, writing, listening, and speaking sections more easily and efficiently. I have no doubt that this book will enable students to become better TOEFL iBT/ TOEIC test takers. I have been working as a TOEFL iBT and TOEFL CBT instructor for more than 15 years in both New York and New Jersey in the US. In addition, I have made a ceaseless and indefatigable effort to analyze the TOEFL iBT/ TOEIC questions on a daily basis in order to become a better TOEFL iBT/ TOEIC lecturer and to meet my students' demands as well. Ultimately, it led me to start and complete this book. I am certain that this book will play a tremendously positive role in helping students boost their TOEFL iBT/ TOEIC scores.