The first published title (code 20655) is for students whom have reached basic/intermediate level and is broken down into 126 independent units which tackle specific grammar topics and pays particular attention to the most common errors and doubts met by students. Explanations are clear and have been graded according to the level of difficulty and give numerous examples. To view a chapter from this book please click here: http://www.esb.co.uk/pdf/gramaticaSM.pdf And now there is a more in depth volume published which covers the level A1/A2 of the CEFR (22698). The structure is clear with grammatical explanations on the left page and the exercises referring to those explanations featuring on the right page.