I'll go ahead and more-or-less second this post. While there are certainly things far more important then your sentance structure and punctuation when it comes to gauging a character, it IS a factor. If I'm visible and I get two tells from two characters I know nothing about, and one says "Greetings Lord Aarn, may we speak?" and the other is "greetings can we speak", I'm totally going to talk to the first guy.

You can overcome bad grammar in many ways, namely by roleplaying a good character. But all things being equal, half-way decent grammar makes for a better character then bad grammar.

Aarn

In a somewhat related comment, try to keep each line of your role at 80 characters or less, so it formats half-way decently. Please? :)