What do you mean four unknowns?

The ancients left four unlucky days in the choice of auspicious days in traditional folk culture: the days when four things were not used, such as being an official, being in office, being close to the people and running an official. These four ominous days refer to the 4th, 7th, 16th, 19th and 28th of each month. These five days are ominous, which means that every once in a while, choosing a home will break seven. These days are the days to break through with plastic ground support. For example, the shape of the moon is the sub-day, the sub-day breaks, and the seventh day is noon, so this month is the fourth, seventh, sixteenth, nineteenth, twenty-eighth and noon, and the rest is pushed. In ancient times, an official took office, saying that the fourth day was unlucky, the seventy-sixth day was the saddest, and the nineteenth day was even more disrespectful. You are stupid, if you don't believe me, you will be ruined, and you won't be an official for long. . .