A dreaded word for many! Anyway…..
For those of you who wish to do “traditional” grammar exercises, I would recommend the Cambridge English Grammar in Use series.
http://www.cambridge.org/it/elt/catalogue/subject/project/item404538/Essential-Grammar-in-Use/?site_locale=it_IT (for elementary learners – but I would suggest this for anyone who would like to review the basics)
http://www.cambridge.org/it/elt/catalogue/subject/project/item404854/English-Grammar-in-Use/?site_locale=it_IT (for intermediate learners – but I would recommend this for most learners who consider themselves advanced, unless you have a really strong grip of English grammar)
http://www.cambridge.org/it/elt/catalogue/subject/project/item404409/Advanced-Grammar-in-Use/?site_locale=it_IT (advanced – for those who already have a strong grasp of English grammar)
Simon