Once waves have been generated,
一旦波浪形成，
新概念英语第四册 Lesson 40 Waves

📚 句中词汇解析

从本句中提取的重要词汇

once [wʌns] 词频1
adv. 一次，一趟;一倍;曾经;一旦; conj. 一旦…就…;一经; n. 一次，一回;
💡 on=one一+ce次 → 一次
"Once in the bloodstream, the bacteria adhere to the surface of the red cells."
细菌一进入血液里，就附着在红细胞表面上。
近义：heretofore, occasionally, onetime, previously, sometimes, thereinbefore
waves
n. 波（wave的复数形式）
近义：surf, surge, groundswell
generated
a. 生成的；发生的

📚 更多「新概念英语第四册」例句

Spiders are busy for at least half the year in killing insects.
蜘蛛至少有半年在忙于吃昆虫。
At noon the spaces between the sensors will hide fluctuations that the computer will not know about, tiny deviations from the average.
正午时分，传感器之间的距离会掩盖计算机无法知道的波动、任何偏离平均值的变化。
Then knowledge began to be accumulated according to a systematic plan.
于是，知识便开始有系统有计划地积累起来。
The lower gun-ports were now below water and the inrush sealed the ship's fate.
下层炮眼已淹没在水里，涌进船舱的水给瓦萨号带来了难以逃脱的厄运。
This may sound fantastic, but it is easily calculated.
这点听起来令人难以置信，但却很容易计算出来。
a trough (the lowest point), a height (the vertical distance from the trough to the crest),
波谷（最低点）、浪高（从波谷到浪峰的垂直距离）