Hello To answer your question, it actually is -지요 ending. However, over time, people have shortened it to 죠 and now both are commonly used. It is a verb ending as you always attach it at the end of the verb It actually has several usages You use it when you know that the person you are talking to knows about it and just mentioning it (maybe to keep the conversation going) = 오늘 날씨가 좋죠?/The weather is lovely today, right? You use it when you and the person you are talking to know about it and just reassure yourself by asking =재미있지요?=Its fun,right? Hope this helps^^