YOU who want to take my class next fall even though it's already full and the university won't open another section--> I'm sorry, but it's not my problem.
YOU who asked me for an urgent favor with a deadline for your non-profit organization and then tell me you're not sure if it's going to be good enough before you even check with the next person down the line who needs the material-->It's not my problem. Say thank you and move on.
YOU who are paying me good money for a translation--> You are my problem. Just tell me what you need and I'll get it to you on time.