青梅竹马 [qīng méi zhú mǎ]
It refers to a boy and a girl playing together since childhood, also to describe a young man and a young woman who have been in love since childhood. It can be used as a preposition, object, definite article or gerund in a sentence.
Story related to the expression:
Once upon a time, there was an ancient street in Nanjing called "Changganli", populated by merchants from the north and the south. There were two neighboring families, both with only one child: a boy and a girl. These two children were so innocent and carefree that they used to play together since they could walk.
One day, as the girl was picking some beautiful wildflowers in front of their house, another boy, holding a bamboo pole several meters long like at the hips like a horse, darted from one end of the lane to the other, shouting, "Run, you big horse!". He was red in the face, sweating and panting, and every now and then he would approach the little girl and ask her if her horse was fast. The girl laughed and clapped her hands in praise of the boy's fast horse. When the boy heard the praise, he rode down the alley several times with his bamboo cane in hand, again triumphant. The girl smiled as she watched the little boy gallop back and forth down the lane.
After a while, the two went back to playing the plum-throwing game. They went out into the yard, hand in hand, throwing the plums to each other. The two were so happy that they played until lunchtime in the dark before splitting up and going home.
Sentences with 青梅竹马：
They grew up together as childhood friends.
Although we used to be childhood friends, but now we are all grown up and have our own lives.