We thoroughly analyzed 40 textbooks for 1st, 2nd, and 3rd grade middle school students and listed the words in order of difficulty: beginner/intermediate/advanced.
It contains basic English vocabulary that all middle school students must memorize, so you can check if there are any words you don't know by looking at the list of 855 essential elementary English vocabulary words designated by the Ministry of Education and then start learning.
(There may be duplicate words depending on the part of speech.) We provide free beginner/intermediate/advanced MP3s recorded by native speakers.
(You can download MP3 from Mother Tongue's homepage www.toptutor.co.kr.)