Read and Learn about grammar:
　

English Club Grammar	This section contains grammar lessons.  Some of the lessons also have grammar exercises for you to test what you have learned.
English Page	A detailed grammar e-book with on-line exercises.
Edunet On-line Grammar	A detailed grammar e-book
BBC Learning English	Have a go on the 'Language Bank'!

Do some grammar exercises :
　

English Club Grammar  ESL Quizzes	Great test your grammar!
Virtual Language Centre	On-line exercises on articles, prepositions, pronouns and verbs
The University of Victoria	Exercises on verbs, nouns, conditionals, punctuation and more for beginners, intermediate or advanced level students..
The English-Zone	Great grammar exercises for students.
The English-Zone Verbs	If you are looking to practice verbs, this is a great page to visit.
Interesting Things for ESL Students	Word puzzles, word games, songs, grammar fun and more.
Self-study quizzes for ESL students	More interactive quizzes for verbs, pronouns, structure, etc. divided into easy, medium, difficult.
Resources for ESL Learners	Resources for English and culture by skill area.  Within each skill area you will find an additional list of links categorized by level- basic, intermediate and advance