定语从句He studied hard and later become a well-konwn writer,___

这是一个非限制性定语从句,which指代He studied hard and later become a well-konwn writer这一整句话,而且很明显有逗号!这是非限制性定语从句的标志,as引导定语从句常解释：正如
而且放句首,而which常在句中而且是一个逗号后面which指代句号前一整句话
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用as不用which，翻译成“正如”