毕业那天我们都不许哭
[bì yè nèi tiān wŏ men dōu bù xŭ kū]
No Crying on Our Graduation Day: It is a vow or hope among friends, classmates or partners, wishing not to express sadness on graduation day, instead keeping only positive and beautiful memories. This is commonly seen in school settings especially at time of partings or graduations.