These two sentences contain multiple meanings. From the sentence of "returning to the wild goose", we can see that the time to go to the frontier fortress this time is spring. When the grass is ripe, the branches and leaves are dry, and the roots leave the earth and float with the wind, so it is called "signing the crown". This sentence is the poet's feeling of falling from the grass. When Cao Peng is mentioned in ancient poems, he mostly laments his own life experience. "Going out to the Han Dynasty" in this poem just reflects the poet's itinerary. Moreover, these three words are very affectionate abroad, which deepens the feeling of occupation. When you leave your hometown, your feelings are always complicated, whether it is because of a difficult home, a difficult country to vote for, or a mission, as this poem says. Regarding the poet's mission this time, he has been in a bad mood, which is different from Sima Xiangru's prestige and demeanor when he was favored by Emperor Wu of the Han Dynasty in the early Han Dynasty and sent to the Southwest. The poet's frustration was related to the political struggle in the imperial court.
Poetry is written in contrasting expressions. "Zheng Peng" is in direct proportion to the poet, and "Returning to the Wild Goose" is in contrast to the poet. In spring, it is a good place for Yanbei to return to its old nest to raise chicks. Facing the desert sandstorm, the poet drifted to the Great Wall like a loose grass, and the situation was very different.