"_s ⇌ or_m / [-spread]+[-spread -lat -labdent -low][b-c-d-g-k-m-n-p-q-t]_u_" . . . "_s ⇌ or_m / [-spread]+[-spread -lat -labdent -low][b-c-d-g-k-m-n-p-q-t]_u_" . .