Lacquer has the dual nature of painting and craft. 漆畫有繪畫和工藝的雙重性。
The doublet nature of this and other lines in the Na spectrum indicates a doubling of the expected number of states available to the valence electron. 鈉光譜中的這條線以及其它線的雙重性指出預期價電子可用的狀態數是雙重的。