n.分層；成層法
These issues can be tackled in applying text stratification theory. 這些問題我們都可以從文本分層理論中獲得相應的解釋與說明。
Stratification in polar waters normally is weak and transient. 極地水域的成層性是微弱而暫時的。
Stratification does not always work, since it often introduces other conflicts. 成層法并非總能解決這類問題,因為這時常會引起另外的矛盾。
