Yan an period的用法和樣例：
例句
- It can be said that Mao Zedong Thought assumed relatively complete form during the Yan'an period.
延安時期那一段，可以說是毛澤東思想比較完整地形成起來的一段。 - How to reform and unify the masses, especially peasants, is the problem which Mao Zedong thought about in that period.
如何改造和團結民眾尤其是農民，這是延安時期毛澤東始終在考慮的問題。
