What are the meanings of "three entrances" and "four entrances" in ancient words describing houses?

The "introduction" of residential courtyards refers to the level of old-style houses and courtyards. There are several rows before and after a house in a bungalow. One row is called "Entering". Take quadrilateral as an example. Siheyuan is a house with a gatehouse in front of the yard.

If it looks like a "mouth", it is called a courtyard; The shape of "sky" is called binary courtyard; The shape of "wood" is called Sanjinyuan. Generally speaking, in a big house, the first entrance is the gatehouse, the second entrance is the hall, the third entrance or the last entrance is the private room or boudoir, which is the activity space for women or their families, and ordinary people are not allowed to enter at will.

Extended data:

Some western historians believe that "traditionalism and opposition to reform have always been the main features of China's lifestyle, and their architectural history has proved this most vividly", which is basically objective. "The laws of ancestors cannot be changed" is the code of conduct of ancient people in China.

The idea of respecting ancestors and observing ancestors requires that the previous architectural forms and structural techniques should not be greatly changed, so it is impossible to change the western style and update the technical means in the history of ancient buildings in China.

In the image of building facade, during the two thousand years from Qin dynasty to Qing dynasty, the three-stage basic shape of abutment, column arch and big roof remained unchanged; In the plane combination, regardless of the use requirements, the monomer and courtyard extend outward along the ground surface to form a layered courtyard.

Baidu Encyclopedia-Courtyard (Courtyard)