The Oxford Guide to Effective Writing and Speaking

Oxford Modern English Grammar

Oxford Advanced Learner's Dictionary, 8th edition (Oxford Advanced Learner's Dictionary)

Oxford Dictionary of English, 2nd Edition

McGraw-Hill Handbook of English Grammar and Usage, 2nd Edition: With 160 Exercises

The Blue Book of Grammar and Punctuation: An Easy-to-Use Guide with Clear Rules, Real-World Examples, and Reproducible Quizzes