The term 'WHAT'S ___ YOU?' can be completed with two different solutions: ITTO and EATING. ITTO is an acronym for 'In The Thick Of It', which is a phrase used to describe someone who is in the middle of a difficult situation. EATING is a verb that means to consume food or drink. Both of these words can be used to complete the phrase 'WHAT'S ___ YOU?', which is a question asking someone what they are doing or what is happening.