undulation
n
(a) [U] wave-like movement or appearance 波动; 起伏.
(b) [C] one of a number of wave-like curves or slopes 波状的弯曲或斜坡
The downs fell in gentle undulations to the sea. 这块丘陵地略带倾斜伸向大海.
🗣️ 情景例句
My mother and father
我父母
It's nice to see you again. Have you changed jobs?