Meaning: There are melons planted under the yellow platform. When the melons mature, many melons grow on the vines. Picking off one melon makes other melons grow better. Picking another melon will make it seem less. If you pick three, there may still be melons, but if you pick all the melons, only the vines will remain.
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The lines "Growing melons under the yellow platform, ripening melons and leaving them alone" are from "Huangtai Melon Ci" written by Li Xian of the Tang Dynasty. The form of this poem is It is a Yuefu folk song, the language is natural and simple, and the meaning is very simple and clear. Using the metaphor of planting and picking melons, he satirizes Wu Zetian, the birth mother, not to maim her flesh and blood or harm her parents and children just for political needs.
Extended information
Although the whole poem "Huangtai Melon Ci" has only six sentences and thirty words, it shows a complete theme. The language is easy to understand and reflects the characteristics of Yuefu folk songs. The whole poem uses metaphors, and the meaning is profound and euphemistic, which can achieve the artistic effect that the speaker is not guilty and the listener is warned.
Li Xian's "Huangtai Melon Ci" is more of a kind of sadness. He has no way to accuse in the poem, because the "enemy" is his mother. In Li Xian's poem, he did not complain too much about his misfortune, but advised his mother to "take three picks and return with the vines in hand" and not to kill all her own children.
Baidu Encyclopedia-Huangtai Melon Ci