an inner sea between the Liaoning and Shandong peninsulas

to give up warfare or crime and return to agricultural work; literally to sell one's sword in the Bohai region

historical multi-ethnic kingdom in Northeast Asia between the late 7th and early 10th centuries, also known as Parhae

literally blue seas where there once were mulberry fields; refers to the great changes brought about by time or the vicissitudes of life. This idiom originates from the [[史记|史記|shi3 ji4]] (Records of the Grand Historian).

describes the appearance of surging and churning waves; turbulent water

the appearance of rising mist or fog; billowing

surging; (of waves) swelling and rolling

The economic region surrounding the [[渤海|渤海|bo2 hai3]], encompassing Beijing, Tianjin, and parts of Hebei, Liaoning, and Shandong provinces