This couplet means that dragons grow in the sea, the sea is where dragons move, and cranes can fly high in the sky, so clouds are like their homes. This is actually a metaphor, which shows that the dragon was born in the magnificent sea and has great strength and ability, and the crane's home in the cloud is a symbol of nobility.
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Anecdote of "the sea is the world of dragons, and the clouds are the hometown of cranes"
After Qi Baishi sent Mao Zedong's paintings, famous collectors such as Zhang Boju and Wang Yue came. Qi Baishi was very happy to talk about sending two works to Chairman Mao. When it comes to the couplet of seal script "The sea is the world of dragons, and the cloud is the hometown of cranes", Zhang Boju can't help crying. It turns out that this couplet is misspelled.
The last couplet was written by Deng, a native of Wanbaishan, Anhui Province in the Qing Dynasty. It was originally called "Heaven is the hometown of cranes" and Qi Baishi wrote "Clouds". Qi Baishi was reminded by Zhang Boju and immediately became nervous. Chairman Mao is a well-read and knowledgeable university expert. Not only is it disrespectful to Chairman Mao, but it is also ridiculous to spread it!
Zhang Boju quickly comforted the old man and said, "Mr. Qi, your word" cloud "is better than Deng's word" sky ". If the first part is' ground', then the word' day' in the second part cannot be moved; But the first couplet is the word' sea', which is just the opposite of your word' cloud'. We don't have to stick to rules. The ancients changed their sentences since ancient times. Chairman Mao may praise you for your good change! " After listening to Zhang Boju, Qi Baishi calmed down.