Overwhelmed by R3

Now I definitely felt overwhelmed with R1 and R2 (both on individual taxes), but I felt like they were do-able sections for me. At some point it was possible for me to conquer them. R3 (C Corp, S Corp and Non-Profit) is just not happening. I have been studying on the first section (C Corp) for the last five hours and am struggling. Some concepts I have down pat, while others are still remaining a complete mystery, and there are a few that aren't even ringing a bell! Ugh! I'm trying my best to just keep taking deep breaths and telling myself it will make sense one day. I just hope that day is before I sit for the exam!