English grammar definitely has taken a casual turn in recent years--think how often you hear a phrase like "Me and Jim went to the movies." But it is still important to learn proper grammar for situations, such as writing term papers or applying for jobs. Online resources make it easier than ever because you can study when you want to and go back to review at your leisure.

Start with basic areas, such as parts of speech and types of sentences (statements, questions, commands). You can find clear, easy definitions and examples on websites such as Scientific Psychic.

Go on to other topics such as adjectives and adverbs, conditionals and conjunctions, participles and prepositions. Many websites, including LEO Network, introduce a wide range of grammar help at no charge.

Get into advanced grammar, with topics such as "advanced unreal conditional" and "modal verbs." You can find free tutorials on these subjects by visiting a website, such as EnglishPage.com.

Take an interactive tutorial--English Grammar 101 is one example. You often pay for these courses, but you receive feedback on your progress through pre- and post-tests or a tutor's help.