English Grammar Lessons is a website where you can revise and exercise your grammar. Grammatical phenomenons such as the tenses, the imperative, the passive voice, the conditionals etc are explained. After a short but a very useful and practical explanation of the specific grammatical phenomenon, the user of the website can access the exercises which are specially designed for this purpose. At the following image you may see an index:
It is quite a useful application and I would recommend it to my students. There is theory as well as practice. A teacher may suggest this application to the students that need more grammar practice or to those who wish to make an overall revise of the English grammar.