city of strong fortification
It's a metaphor for a city that defends solidly and is not easy to break.
Idioms and allusions
[source]: Chen Shou's biography of Xinpi in the annals of the Three Kingdoms, Wei annals, said: "the art of war says that those who have Shicheng Tangchi with one million armor but no millet can't defend it."
Discrimination of words
We have shichengtangchi, the enemy can't pass.
city of strong fortification
stick together in life and death - shēng sǐ xiāng yī
a perfect match between a man and a girl - láng cái nǚ mào
reconcile oneself to one 's situation - suí yù ér ān
attachment to the things and people related to a loved one - wū wū zhī ài
a bell with a wooden clapper -- used figuratively for education - jīn kǒu mù shé