The idea is that king k and queen q are both near some location r with a small displacement so k = r + dk and likewise q = r + dq. Then also so around s for man m and woman w, so m = s + dm and w = s + dw. The idea then is that dk = dm and dq = dw, this is the ”semantic structure.” The displacement is the same. So k - m + w = r + dk - dm + dw = q. It would have been cool, but it seems what really happens is queen gets embedded close to king, and the nearest word is just queen. I guess it does show that dk = dm and dq = dw though, but it could also be that dk = dq, and dm = dw.