Let me discuss the reasons why we fast. Of course, we understand that God expects us to fast, Jesus fasted, most others used by God fasted. But do we understand why?
One correct answer is to get an answer of some kind to our prayers. What are these common things we pray for?
We often pray for successes and breakthroughs. A father may pray to change the heart of his employer or business partner in order to increase his personal gain and thus have more money to increase his family's comfort. A young son might ask God to change his family members so that they would not have to fight bitterly every night. A young woman could be praying for God to change the character of a guy she fancies from one of loose morals to somone embracing purity. And indeed, there is nothing wrong with asking the Lord God for such things.
But that is not the upper limit of our capacity to pray while fasting. Asking for events and situations changed to be granted to us should not be the point of fasting. Fasting and its related prayers ought to be the thing that compels us to seek God for the purpose of changing ourselves and the response we have towards our situation.
The father may instead pray that God helps him overcome his reliance on alcohol and cigarettes, which over the course of a year would save his family thousands. The son could instead ask God to change him and his way of responding instead so that his situation can be used for the benefit of God. The woman could also instead ask the Lord to change her heart, in that instead of pining after the guy she fancies, she instead looks for opportunities to introduce him to Jesus and that his life is changed regardless of the outcome for any relationship she may want.
Granted, we can't change people. But fasting and prayer should not just be about us asking God to change the world and people around us to be more pleasant both for Him and for us. Fasting and prayer should be about us asking God to take over our hearts and lives and repurpose us in such a way that brings Him the most glory through how God uses us to change the people around us.