sentences:  It descended back into the water, with the shiny sword in its mouth, and for a long period a flickering light was said to have been seen from beyond the muddled depths of the lake.From then on, people renamed that lake to Hồ Gươm (Sword Lake) or Hồ Hoàn Kiếm (Lake of the Returned Sword).A few historians believe that the Thuận Thiên sword was an expedient of Lê Lợi's strategist Nguyễn Trãi, regarding it as a ploy to gain legitimacy for Lê Lợi to lead an uprising against the Chinese.