[ Daim ntawv qhia ] ntawv nyeem

☞ x ≔ Daim ntawv qhia tshiab.
x muab: ‘a’ rau: ‘b’.
☞ y ≔ x ntawv nyeem.
✎ sau ntawv: y, tsum.
(Daim ntawv qhia tshiab) muab:‘a’ rau:‘b’