渤海 but⁶ hoi² {Bó Hǎi}

1. Bohai Sea, or Bo Hai, between Liaoning and Shandong
2. Parhae, Korean kingdom in Manchuria and Siberia 698-926

渤海灣〔--湾〕 but⁶ hoi² waan¹ {Bó hǎi wān}

Bohai Bay

渤澥桑田 but⁶ haai⁵ song¹ tin⁴ {bó xiè sāng tián}

1. lit. blue seas where once was mulberry fields (idiom, from 史記, Record of the Grand Historian); time brings great changes
2. life's vicissitudes