下雨了谁为我撑下雨了我为你撑
[xià yŭ le shéi wéi wŏ chēng xià yŭ le wŏ wéi nĭ chēng]
The literal translation of this is 'In rain, who would carry an umbrella for me? In your rain, I would be there to hold an umbrella for you', representing the idea of reciprocating care or help in a relationship.