The undulating waves of the open sea are generated by three natural causes: wind, earth movements or tremors, and the gravitational pull of the moon and the sun.
undulating v. (fml.) to move or be shaped like waves that are rising and falling 波动，呈波浪状起伏
- a field of wheat undulating in the breeze
- The artist perfectly captured the look of the undulating waves in the painting.这位艺术家在画中完美地捕捉了起伏的波浪的景象。
- We watched the undulating waves from the deck of the cruise ship.我们在游轮的甲板上观看着起伏的波浪。
- The surface of the lake began to undulate as the wind picked up. 随着风力增强，湖面开始泛起波纹。
| undulating hills 起伏的山峦；连绵起伏的小山 | The road wound through miles of undulating hills and green pastures. 道路穿过数英里连绵起伏的小山和绿色牧场。 |
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be generated by 由…产生/生成
- The undulating waves of the open sea are generated by three natural causes.开阔海域起伏的波浪由三种自然原因产生。
- Electricity is generated by various sources, including coal, wind, and solar.电力由各种来源产生，包括煤炭、风能和太阳能。
tremor n. 1. a small earthquake in which the ground shakes slightly 轻微地震
- Minor earth movements or tremors are common in that fault zone.轻微的地壳运动或震动在该断层带很常见。
- The earth tremor lasted only a few seconds, but it was enough to rattle the windows. 那次轻微地震仅持续了几秒钟，但足以震得窗户嘎嘎作响。
tremor n. 2. a slight shaking movement in your body that you cannot control, especially because you are ill, weak, or upset 颤抖
- There was a slight tremor in his voice.
- She felt a tremor of fear run through her.
- There was a slight tremor in her voice as she began to speak about the incident. 当她开始谈论那起事件时，声音略带颤抖。
- Parkinson's disease often causes an involuntary tremor in the hands. 帕金森病经常导致手部不由自主地颤抖。
gravitational adj. related to or resulting from the force of gravity 重力的
- The gravitational force between the Earth and the Moon keeps the Moon in orbit. 地球和月球之间的万有引力使月球保持在轨道上。
- The gravitational pull of Jupiter affects the orbits of many asteroids.木星的引力影响着许多小行星的轨道。
| gravitational field 重力场；引力场 | An object within a planet's gravitational field will experience a force pulling it toward the center. 处于行星引力场内的物体会感受到一股将其拉向中心的力。 |
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| gravitational pull 引力作用；重力拉力 | The gravitational pull of the sun is strong enough to hold the entire solar system together. 太阳的引力强大到足以将整个太阳系维系在一起。 |
Once waves have been generated, gravity is the force that drives them in a continual attempt to restore the ocean surface to a flat plain.
restore sth. to sth. 恢复；使（某物）恢复到（某种状态/位置）
- The committee is working hard to restore the old church to its original glory. 委员会正努力使这座古老的教堂恢复往日的辉煌。
- The government promises to restore the economy to full strength.
- She was hoping that the Mediterranean climate would restore her to full health.
- The engineers worked to restore the damaged area to a flat plain for construction.工程师们努力将受损区域恢复到平面以进行施工。