In Feng Shui, what do standing and sitting directions mean?

The sitting direction is the direction of an existing house. The rear is sitting and the front is facing.

The standing direction refers to choosing the best sitting direction before building a house. This should be selected based on a comprehensive analysis of the surrounding environment of the house and the luck at the time of building the house.

In Yinzhai Feng Shui, the vertical direction refers to the direction of the tombstone.