AceShowbiz -

Harry Styles can't just ignore the signs fans hold during One Direction's concerts, especially those that are grammatically incorrect. At the band's show in Philadelphia recently, he kindly took the time to give a grammar lesson after he noticed there's something wrong with a sign a concertgoer was showing from the audience.

The sign in question read, "Hi Harry! Your so nice." The 21-year-old singer grabbed it, brought out a black marker and turned the "your" to "you're." He added his autograph before returning the sign to its owner, who excitedly shared via Twitter a picture of the corrected version.

"Thank you so much @Harry_Styles for signing my poster and also correcting my grammar!!" the fan wrote.

Thank you so much @Harry_Styles for signing my poster and also correcting my grammar!! ���°�¯�¿�½�¯�¿�½�¯�¿�½���¢�¯�¿�½���¤���¯���¸�¯�¿�½ pic.twitter.com/8v9xM6umbn

— Taelor Ford (@taelor_ford) September 2, 2015

The Philadelphia concert was part of One Direction's "On the Road Again" tour that came in support of their latest album "FOUR". The boys will wrap up the North American leg of the trek later this month.

In between their tour dates, the four-piece has been working on their fifth studio effort. They plan to release it in the coming months and start their year-long hiatus next year.