If you're Korean and want to hone your English, why not use a fairly obscure hundred year old text about the flowering of modern Hebrew literature?

Wow, this is weird.

"Webster's edition of this classic is organized to expose the reader to a maximum number of difficult and potentially ambiguous English words. Rare or idiosyncratic words and expressions are given lower priority compared to "difficult, yet commonly used" words. Rather than supply a single translation, many words are translated for a variety of meanings in Korean, allowing readers to better grasp the ambiguity of English, and avoid using the notes as a pure translation crutch. Having the reader decipher a word's meaning within context serves to improve vocabulary retention and understanding. Each page covers words not already highlighted on previous pages. If a difficult word is not translated on a page, chances are that it has been translated on a previous page."

The Renascence of Hebrew Literature (1743-1885) by Nahum Slouschz (Webster's Korean Thesaurus Edition)