Answer:
The ventral side is towards the belly side
The Dorsal side is back to the belly side
Anterior is Before the belly side
Posterior is after or coming after to the belly side.
Explanation:
The ventral side is associated with the animal or a person belly side which related to the organism digestion and respiratory organs.
The anterior is the before or in front of side position which is associated with the front line of an organism.
The posterior side is related to the after side or it is opposite to the anterior position of an organism.
It is depend on the organism position, that these sides are related to each other in some instances. In some cases these are orthogonal in some times.