【正确答案】:
IT IS NOT EASY TO PROVIDE A CLEAR DEFINITION OF A CONCEPT, WHICH REQUIRES A PROLONGED PROCESS OF INTELLECTUAL EXPLORATION.
【题目解析】:本题考查对定语从句的翻译。分析句子结构,此处定语从句的先行词为主句的一部分,即to provide a clear definition of a concept“对于某一概念给出明确的定义”,题干译文中先行词位于句首,而通常为了避免歧义,引导词需要紧跟先行词,故此处需要改为it作形式主语的主语从句,使先行词位于引导词which之前。