What is the last sentence of "When will the bright moon shine on the ditch"?

The last sentence is: how can the moon shine on the ditch?

"I shine on the moon with all my heart, and the moon shines on the ditch", which means that I am kind to you, but you are indifferent and ungrateful. My sincere efforts have not been rewarded and respected.

Source: Gao Ming's Pipa Story in Yuan Dynasty

Quotations: The 19th chapter of Romance of the Gods: Let's talk about da ji's deep hatred: "Such a man! The light one is like this. I entrusted my heart to the moon, but the moon filled the ditch. On the contrary, he humiliated me. If I discipline you to pieces, I will hate you to death! "

Quotation: "Surprise at the First Moment" Volume 36: "The woman has never booked Du Lang face to face, but only listened to him while coaxing, so it should be counted. With his words, she believed, and the Tao was determined from now on, so that she could meet Du Lang and fulfill her long-cherished wish. Exactly: I will trust the moon with my heart, but who knows that the moon shines on the ditch? "

Extended data:

Creative background:

In the Yuan Dynasty, the social situation changed greatly, and the situation of scholars fell from the sky to the ground. The imperial examination in Yuan Dynasty was interrupted for more than 70 years. At the end of Yuan Dynasty, the imperial examination system was good and bad. This makes many scholars lose their position in the world, and their social status drops sharply, resulting in the saying of "nine sons and ten beggars". In connection with this, the tragic works condemning the scholar's betrayal of marriage have gradually lost their realistic pertinence. Scholars with low status have become the object of sympathy.

Therefore, the literati images in Yuan Zaju are either mediocre and timid, or pedantic and introverted. Although most of them lack luster, they are rarely used as whipping objects. By the end of the Yuan Dynasty, people felt more and more sorry for the scholar whose status could not be improved, and the works praising the scholar's sincerity gradually became the mainstream of traditional Chinese opera. The Story of Pipa depicts the image of Cai Bojie with sympathy and tolerance, reflecting the social model at that time.