Left / Right convention: "left" and "right" are always
from the person's point of view — not yours. In the illustration,
the figure faces you and waves with their left
arm.
For each pair, watch the Source, Target,
and Overlap videos, then tick every body part that moves
differently between source and target. Multiple body parts may be
selected. Each batch contains 30 pairs — refresh the page to load a new
batch.