"shattered glass" is an idiom from a historical story, which originated from Thirty-one Years of Zuo Gong. "shattered glass" means trying to cover up the truth of bad things, but the result is more obvious. This idiom can be used as predicate, object and attribute in a sentence, which contains derogatory meaning.
The origin of idioms: you can't get a name, or you want to get a seal (through "Zhang") to punish evil and promote good. Song Sima Guang's History as a Mirror The Sixteen Years of Emperor Taizong's Zhenguan: Fear of others, furious, shattered glass, no advantage in competition! Ba Jin's About Home: But the sentence is useless. In others' eyes, I have repeatedly declared that it is shattered glass.
Idiom implication
In the above story, Cui Yao, who killed historians, killed two upright and unyielding historians in succession to cover up his crime of killing Qi Zhuanggong. This shameless behavior not only does not excuse itself, but makes its ugly behavior more obvious in front of people.
Shattered glass is the kind of behavior that tries to cover up the bad things, but the result is more obvious. This stupid and ugly behavior exists not only in ancient times, but also in the real life of today's society. Life is long and mistakes are inevitable. It doesn't matter if you make a mistake. The key is to know your mistakes and correct them, instead of trying to cover up your crimes and make mistakes again and again.