low-frequency cycle

例句：

1. 1.The low-frequency cycle of the earth's rotation is responsible for the tilt of the planet's axis.
   地球旋转的低频周期是导致地球轴倾斜的原因。
2. 2.In this study, we investigated the low-frequency cycle of human sleep patterns.
   在这项研究中，我们研究了人类睡眠模式的低频周期。
3. 3. The low-frequency cycle of the sun's movement affects the timing of the seasons.
   太阳运动的低频周期影响了季节的时序。