sweetheart

The high school sweethearts got married shortly after they both graduated from university.

(Chinese) 这对高中时期的恋人在大学毕业后不久就结婚了。

He sent a bouquet of red roses to his sweetheart for their first anniversary.

(Chinese) 他在一周年纪念日给他的心上人送了一束红玫瑰。