Generally speaking, a traditional tomb will have a main tomb (burying the remains) and at least one auxiliary tomb. Take ancestral graves as an example, there may be several auxiliary graves. However, no matter how many auxiliary graves there are, there will also be a main grave. Others are generally used to occupy area. To put it bluntly, it is to occupy space and not let others be buried nearby.
Judging the gender of the owner of the tomb depends on whether the auxiliary tomb (the main and auxiliary tombs) is located on the left or right of the main tomb. In short, the correct way to judge is to look out in front of the grave hall (not at the tombstone, but at the back), so that the left hand is left and the right hand is right.
And if there are multiple sub-tombs, how to judge which one is the main sub-tomb? It's actually very simple. Generally speaking, auxiliary graves burn incense and light candles. Only the auxiliary grave will worship with chicken and candy.
If several auxiliary graves worship in this way at the same time, neither the front (front soil) nor the back (back soil) is the main grave. Slightly biased. Generally, the auxiliary tombs around will not worship.
There is another situation, if there is only one auxiliary tomb, and it is directly behind, I don't know how to judge this.