This sentence comes from Nalan Xingde's poem "Hua Tang Chun" in the Qing Dynasty. It should be completely read: A pair of people from one generation to another in a lifetime, competing for education and ecstasy in two places? Love each other but not love each other, who is the spring of heaven? ! It is easy to beg for blood from a blue bridge, but it is difficult to run away from a blue sea with medicine. If you visit each other and drink Oxford, you will forget your poverty.
It means that a person will only love one person in his whole life, and will never leave him until life or death. together