The teacher Training CELTA course covers the general principles of teaching adult classes at all levels, from beginners to post-intermediate: most students throughout the world fall into this category. The teaching methods and techniques covered by the course are those used in recognised English language schools all over the world. The course is only suitable for those who are already proficient in English (ie. those with a level of written and spoken language equivalent to C2 on the Common European Framework of Reference for Languages (CEFR), or IELTS level 8). Potential candidates must also be at least 20 years old and be eligible for higher education.