The Extreme English Advanced course is a set of 9,800 words and expressions at the advanced level, corresponding to well-developed linguistic skills and communicative competence of an educated native speaker. This course includes vocabulary items required for the following exams: Cambridge Certificate in Advanced English (CAE), International English Language Testing System (IELTS) and Test of English as a Foreign Language (TOEFL). Mastering this set of vocabulary items allows the learners to understand long and complex statements and texts and to formulate their own opinions on any given topics in a clear and coherent way. These skills correspond with the C1 level of The Common European Framework of Reference for Languages.