Cheng Yi (chéng yí 程颐) was a Chinese philosopher born in Luoyang during the Song Dynasty. He worked with his older brother Cheng Hao (chéng hào 程灏).
On a heavy snowy day, there was a young man named Yangshi went to visit his teacher Cheng Yi. He found his teacher was sleeping when he arrived at the house. So he waited in the snow because he didn't want to wake his teacher up. When his teacher finally got up and the snow was very thick. Since then people use this idiom to say some one respect his teacher.

In the Jin Dynasty (jìn cháo 晋朝,265-420), a man called Yue Guang (yuè guǎng 乐广) once invited a friend to have a drink at his home. When the friend lifted his cup, he saw a small snake in the wine, yet he forced himself to drink. Back home, the friend recalled the incident, and felt so disgusted that he fell ill. Hearing about this, Yue Guang invited his friend again. He asked him to sit in the same place and drink. Then his friend saw that the image of the snake in the cup was actually the reflection of a bow hung on the wall. Realizing this, the friend recovered quickly.

每日惯用语（49）

A 吃哑巴亏
Suffering loss without redress

【发音】chi ya ba kui
【释义】受了损失却不能说
【例1】因为证据不足，他没有办法起诉，吃了哑巴亏。
            Because of lack of proof, he could not bring a case to court and suffered loss without redress
【例2】他不甘于吃哑巴亏，私下报复了打他的人。
            He was unwilling to suffer loss without redress so that he revenged the one who attacted him secretly.

A man who raised sheep once noticed there was a hole in the walls of his sheepfold. But he neglected to repair it. A few days later, several sheep were missing. His friend advised him: "It is not too late to mend the sheepfold."

"Wang Yang Bu Lao" or "Mending the sheepfold after the sheep have been stolen" advises us that even though we have suffer a loss, it is never too late to take steps to prevent further losses.
 

每日惯用语（48）

A 扯淡
to utter nonsense

【发音】chě dàn

【释义】胡说，说假话，说废话

【例1】 别扯淡，说真话。(bié chě dàn)
Don’t utter nonsense, tell the truth.

【例2】 他只会扯淡，从来不说有用的话。（tā zhǐ huì chě dàn còng lái bù shuō yǒu yóng de huà.）