有你阳光跟灿烂有你黑夜不黑暗
[yŏu nĭ yáng guāng gēn càn làn yŏu nĭ hēi yè bù hēi àn]
With You Sunny Days Are Brighter and Dark Nights Less Gloomy implies that the other person has a significant positive impact on every aspect of one's life, making hardships lighter and joys fuller, highlighting importance and gratitude.