It's easy to dress modestly and act godly, yet look rotten on the inside. (Think of a shiny, beautiful, perfectly-looking, pear. You bite into it and realize that it's not what it seems. The inside is rotting and little worms have found their abode.)
i.e: there can be a young lady who dresses very modest, but she isn't serving the Lord with all her heart. She disobeys her parents, loses her patience easily, and in fact, when she isn't in church, it's hard to tell whether or not she's a child of God.
Examine yourself. What are your virtues? And what areas do you need to work on? Think about it.