Slang bahasa Inggris di dunia maya
All in one toefl grammar
Tips dan strategi IELTS : reach the peak
Mosaic 1 : listening/speaking
Kamus Inggris Indonesia
Basic English grammar : understanding tenses, subject, and verb agreement
The McGraw-Hill Handbook of English grammar and usage
TEFLIN : teaching English as a foreign language in Indonesia Journal
Thesaurus of slang
English idioms exercises on phrasal verb