The mature stage of the theory of literary fiction is in the modern period.
文学虚构理论真正成熟的阶段是在现代主义时期。
The 19th century is a mature period of educational theory in the western history.
在西方教育思想史上，19世纪是西方近代教育理论趋于成熟的时期。
The 19th century is a mature period of educational theory in the western history.
在西方教育思想史上，19世纪是西方近代教育理论趋于成熟的时期。
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