Michael Swan is a writer specializing in English Language teaching and reference materials. His publications include Practical English Usage (OUP), How English Works (OUP) and The Good Grammar Book (OUP). He is also co-author, with Catherine Walter, of the Cambridge English Course series. His most recent books are Grammar (in 'Oxford Introductions to Language Study') and Grammar Scan (OUP), a collection of diagnostic language tests written in collaboration with David Baker. Michael's interests include pedagogic grammar, mother-tongue influence in second language acquisition, and the relationship between applied linguistic theory and classroom language-teaching practice. He has had extensive experience with adult learners, and has worked with teachers in many countries.