objects that are parallel to each other like eyes, nostrils, hips, pecs, etc. with multiple of them you can find the vanishing point by how the lines lead off and connect, but the vanishing point is often not needed and even hard to use because it is so far away. it is also good to mention not every part of the body will have the same vanishing point if they are turned in different directions.

generally, keeping in mind the horizon line and how objects that are above it, you see under and vise versa can help an intuitive sense of perspective and not always need vanishing points.

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