I would say that "what it is" is part of a statement. It is used when you, or someone else knows what something is, so you don't need to ask anyone.
"What is it?" is the question version, which you ask someone when you don't know what something is.
"What it is like to be liked!" (Statement: Here, you already know what it is to be liked and you are making a statement that it pleases you.)
"What is it like to be liked?" (Question: in this case you don't know what it is to be liked, and so you have to ask someone.)
Do you have any examples from what you are reading?