例句與造句

1. This is due to the fact that the extraordinary wave propagating through a birefringent crystal possesses a Poynting vector that is not parallel to the propagation vector.
2. Since the propagation vector \ vec { k } is proportional to the photon's momentum, the transverse propagation direction ( k _ x, k _ y, 0 ) must remain the same in both regions.
3. It's difficult to find propagation vector in a sentence. 用propagation vector造句挺難的