<p>can i provide some info here and withold some info that isn't applicable? (like first language stuff). i was just wondering if this is one of those fill all or leave all of it blank. thanks</p>
<p>Since it's optional you can do whatever you want. However, if you answer some questions but not others, people who read your application may wonder about the questions you didn't answer. If you don't want to draw attention to the ones you don't answer, don't answer any of the optional questions.</p>