Birefraction
双折射
🗣️ 情景例句
Yes, caring.
是的 ，关心。
His heart cannot be pure whose tongue is not clear.
嘴不净者心不纯。
The wall behind looks a bit grey and dull. What can we do to make it look less ugly?
后面那堵墙看起来有点暗。我们能不能让它漂亮点？