You'll need to earn a 3.5 out of 5 points before the next quiz will open. You can take this quiz as often as you like, and you will get feedback on each of the questions after each attempt, but the questions will change each time you take the quiz.

However, the quiz will always cover the same grammar issues in the same order:

As you will note, the list above contains hyperlinks to a tutorial (and often a practice quiz at the bottom of each lesson) on each grammar issue. If you are having trouble with a particular element of grammar, read over the tutorial and perhaps take the practice quiz at the end before you re-attempt the quiz. This will be the most effect way to earn a passing grade on the quiz and, more importantly, improve your grammar.