How to use "instance" in a sentence

Think if you can, of a single instance in which a plainly written provision of the Constitution has ever been denied

For instance, why may not any portion of a new confederacy a year or two hence arbitrarily secede again, precisely as portions of the present Union now claim to secede from it? All who cherish disunion sentiments are now being educated to the exact temper of doing this."

That child, for instance - you've no idea how much she costs