Did you ever thought about this: what if god(in any religion)know every languages and accept every prayers we ask and just he don't know one thing which is the word called negative such as (can't ,won't, shouldn't, wouldn't, etc)

As our mind is been constantly discouraged for thinking every thing can be achieved..alot people's prays in kind of this way.."god pls don't make me fail in the exam".."pls don't let me suffer this much and all".

Can u imagine if god is ready to give you everything u ask how he may hear these prayers..
Like this:
"God make me fail in exam"
"God pls let me suffer"

Hope you can understand how it works..with confidence if you ask anything in a positive manner you will receive.