Each section opens with a lively presentation page which introduces the point of grammar. Grammar explanations are short, clear and easy to remember. Colour is used to highlight grammatical contrasts. Each grammar explanation is followed immediately by an activity, so that students can practise before moving on to the next explanation. Engaging practice activities include Internet exercises which enable students to see how language is used in real life, Do-it-yourself exercises which encourage students to discover how grammar works, and personalisation activities which allow students to use the grammar to talk about themselves. There are 'More practice' and a revision test at the end of each section. OEGC Intermediate has units at two levels. Some, marked 'Revise the Basics', revise elementary points of grammar which may still cause problems; units marked 'Level 2' are more advanced. Each level has a free downloadable Teacher's Guide. These lesson-by-lesson guide Michael Swan is a writer specializing in English language teaching and reference materials. His interests include pedagogic grammar, mother-tongue influence in second language acquisition, and the relationship between applied linguistic theory and classroom language-teaching practice, and he has published a number of articles on these topics. Michael Swan: ELTons 2014 British Council lifetime achievement award winner. Catherine Walter: ELTons 2016 British Council lifetime achievement award winner.