19.In a period characterized by theabandonment of so much of the realistic tradition by authors such as John Barth，Donald Barthelme，and Thomas Pynchon, Joyce Carol Oates has seemed at times determinedly old-fashioned in her insistence on the essentially mimetic quality of her fiction.

(特殊结构characterized by…——以…为特征)

尽管处于一个以抛弃大量现实主义传统(以作家约翰·巴思、唐纳德·巴塞尔姆和托马斯．品钦为代表)为特征的时代，乔伊斯·卡罗尔·欧茨因为坚持自己小说本质上模仿的特点，有时候看起来是一个坚定的守旧派。

分句1: characterized by the abandonment of so much of the realistic tradition byauthors such as John Barth，Donald Barthelme，and Thomas Pynchon,

分句2: Joyce Carol Oates has seemed at times determinedly old-fashioned in herinsistence OD the essentially mimetic quality of her fiction．

分句1 做时间状语“In a period”的后置定语，补充修饰period，相当于省略了“which was”的定语从句

分句2 是主句