四よん当とう五ご落らく

expression

sleep four hours and pass, sleep five hours and fail

A set phrase from the era of intense university entrance exam cramming, meaning that sleeping only four hours leads to success while five hours of sleep leads to failure. Used to emphasize the extreme study ethic expected of exam candidates.

• 受じゅ験けん生せいの間あいだでは「四よん当とう五ご落らく」という言こと葉ばがよく使つかわれていた。

  Among exam candidates, the phrase 'four-pass, five-fail' was often used.

• 「四よん当とう五ご落らく」の精せい神しんで、彼かれは睡すい眠みん時じ間かんを削けずって勉べん強きょうした。

  With the 'four-pass, five-fail' mindset, he cut down on sleep to study.