What's the story of the poems scrutinized by Wang Anshi and Jia Dao?

It is said that when the poet Wang Anshi wrote "Dengguazhou", he first wrote "Spring Breeze Arrives in Jiang Nanan". Later, he thought the word "to" was not good, so he changed it to "Guo" and then changed it to "Jin" and "Man". It has been revised more than ten times, and they are not satisfied. Finally, inspired by the poem "When the spring breeze comes, the green lake rises again", he decided to use the word "green".

The word "scrutiny" comes from the story of Jia Dao, a poet in the Tang Dynasty, who tempered his poems, meaning to ponder repeatedly.

One day, Jia Dao rode a donkey in the street of Chang 'an, the capital of China, and casually recited a poem, including two sentences:

"Birds perch on trees by the pool, and monks push the moon down the door."

Jia Dao felt that the word "push" in the poem was not properly used. He wants to change the word "push" to "knock", but he doesn't know which word is good at the moment. So, while thinking, I repeatedly pushed the door and knocked at the door with my hand. Pedestrians in the street were surprised to see Jia Dao's expression.

Han Yu saw it and said angrily to Jia Dao, "Why don't you ride a donkey with your head down and look ahead?"

Jia Dao was surprised, hurriedly got off the donkey, saluted Han Yu, and said the poem he had just got from the donkey again. Because he thought of the words "push" and "knock", he concentrated on thinking, so he avoided answering.

After hearing this, Han Yu turned anger into joy. After thinking for a moment, he said, "Good typing! When everything is asleep and quiet, knocking at the door is even more dead of night. "

Jia Dao repeatedly thanked him with a poem entitled "Monk Knocking at the Door".