Mark is a teacher, trainer and materials writer. He has written supplementary materials for Global, Straightforward and onestopenglish.com. He has a special interest in senior learners and co-wrote two articles on the subject for the journal English Teaching Professional. He has been collecting curious Spanish vocabulary for over twenty years and managed to turn it into something useful by co-authoring a bilingual English-Spanish Dictionary of Slang with his wife Almudena called Word up! (Pons, 2009).