动 （开展； 发挥） spread out，develop，amplify；形 （多余） redundant，superfluous；名 low and smooth land，hillside，marsh ；

[例句] 色泽是反射和衍射的综合效果. Lustre is the integral effect of reflection and diffraction.

[例句] 在这种情况下,据说,波发生了衍射. In this case the wave is said to have been diffracted.