An Indian Student Studying Late At Night At The University Of Madras In Tamil Nadu, 1905. Students use to tie their hairs to a nail in the wall to prevent themselves from falling asleep while studying late at night. It’s a traditional method. Chinese people has been using it for two millennia, which was firstly recorded in the chronicle Book of Han (汉书) in 1st century (famously “头悬梁”). It simply means that all your achievements need your sacrifice.
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