n.分层；成层法
These issues can be tackled in applying text stratification theory. 这些问题我们都可以从文本分层理论中获得相应的解释与说明。
Stratification in polar waters normally is weak and transient. 极地水域的成层性是微弱而暂时的。
Stratification does not always work, since it often introduces other conflicts. 成层法并非总能解决这类问题,因为这时常会引起另外的矛盾。
