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ESL Grammar Reference & Practice
Mr. F's Ultimate
Grammar Guide
Clear explanations, helpful examples, and practice questions for every grammar unit. Click any unit below to get started.
Mr. F — Your Grammar Teacher
About Mr. F
Mr. F has spent over 30 years teaching English in Korea, Taiwan, Saudi Arabia, and Japan, working at companies, colleges, and universities along the way. Over that time, he has noticed that the same grammar questions come up again and again — no matter where in the world his students are from.
This site is his answer: a clear, practical grammar reference built from real classroom experience, with explanations written the way he would explain things to you in person. Every unit includes practice questions so you can test yourself and track your progress as you improve.