periodic waves

例句：

1. 1. The ocean has a rhythmic pattern of periodic waves.
   海洋有节奏的周期性波动模式。
2. 2. The sound of the waves is like a melody that repeats in cycles.
   波浪的声音像一首循环的旋律。
3. 3. The scientists observed the periodic waves of the tides.
   科学家们观察到了潮汐的周期性波动。