It's 'useless' trying to change her mind. = It's 'useless' to try to change her mind.
Drugs are 'useless' in treating the condition.
I made a 'useless' attempt at fixing the leak.
(..) Anger. Unload the daydreams. I ordered extra, in case things get slow in class. Might come in handy. If this new school is full of boring, useless classes. Which it probably will be. Oh, Sadness. I've a super important job just for you. - Really. - Uh-heh. Follow me. (..)2015 Inside Out