What role does the word "You" in the first couplet of Du Fu's poem "Jiangcun" play in the whole poem? And how does the couplet express the poet's feelings?

The word "everything is quiet" in the second sentence of this poem's first couplet is a reminder of the whole poem. The middle four sentences are closely attached to "everything is quiet" and all the way down. Swallow in the beam, when it comes and goes, is free and comfortable; Bai Ou on the river, far and near, goes hand in hand. From the poet's eyes, both swallows and gulls have an interest in forgetting the machine and being suitable for the music group. Things are so quiet, and the interest of personnel especially makes the poet happy: the old wife draws paper for the infatuation and innocence of chess, looking at it and being amiable; The innocence of a child knocking on a needle as a hook is lovely. Chess is best for summer, Qingjiang is just fishing, and the village is happy, and everything goes well. After a long period of separation, how can the poet not feel happy and satisfied when he regains the joy of his family and children? The closing sentence "But there is an old friend who provides rice, and what more can I ask for?" Although it is a happy word on the surface, there is a lot of bitterness in the bones. Saying "but there is" cannot guarantee that there will be; To say "what do you want more" means that you have already asked for it. Du Fu really didn't forget that his leisurely life in front of him was built on the basis of "an old friend for rice". This is a very sensitive tender point. Once there is a problem with the distribution of rice, nothing can be discussed. Therefore, we can say that the last two sentences are not so much lucky words as bitter feelings. A generation of poets, who lived in poverty and depended on others, revealed such sad words while they were temporarily settled, which was really a strong accusation against the feudal ruling class for destroying talents. In the four sentences of Zhonglian, from the aspect of material state and human feelings, I wrote enough about the quiet things in Jiangcun. Then, at the end of the sentence, I used the sentence "What else can I ask for" to close the "everything is quiet" and collected a theme, which was the simplest and most secure.