柠檬吃着西瓜甜西瓜吃着柠檬酸
[níng méng chī zhe xī guā tián xī guā chī zhe níng méng suān]
The literal translation is 'lemon eats watermelon sweet, watermelon eats lemon sour,' which symbolizes a paradoxical situation where contrasting feelings coexist, often related to mixed emotions like happiness and envy or jealousy.