What do the words "the official catches people at night" and "the old woman serves" in the poem "Shihao Official" show? What thoughts and feelings does the whole poem reflect?

The sentence "arresting people at the night of being an official" is the outline of the whole article, and the following plots all come from here. Saying "arresting people" instead of "recruiting soldiers", "counting soldiers" and "recruiting soldiers" is exposed and criticized in the truthful description. Coupled with the word "night", the meaning is even richer. First, it shows that the government's "arresting people" often happens, and people hide or resist during the day and cannot "catch" them; Second, it shows that the means of "arresting people" by county officials is vicious, and they make a sudden attack at night when the people have fallen asleep. At the same time, the poet threw himself into Shihao Village at dusk. Several hours have passed from dusk to night, and of course he has fallen asleep by this time. So he didn't take part in the later activities, but heard them through the door. The phrase "the old man crosses the wall and the old woman goes out" shows that the people have suffered from Ding for a long time and have no peace day and night; Even in the middle of the night, I still fidgeted. As soon as I heard the noise outside the door, I knew that the county officials had come to "arrest people" again. The old man immediately fled over the wall, and the old woman opened the door to deal with it. The old lady was afraid that her widowed daughter-in-law would be caught and starve her grandson, so she had to come forward: "Although the old lady is weak, please come back at night. I'm in a hurry to wait in the river, and I have to prepare breakfast. " Exposing the cruelty of feudal rulers reflects the profound disaster brought to the people by the war caused by the Anshi Rebellion in the Tang Dynasty and expresses the poet's deep sympathy for the working people.