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
I promise I won't leave early.
我发誓我再也不会早走了。
About ten minutes.
大约10分钟。
if there is any effect of noise upon mental health it must be so small that present methods of psychiatric diagnosis cannot find it.