非限制性从句,是一种提供额外信息但不改变句子核心意义的从句。即使去掉该从句,句子的主要意思仍然完整。非限制性从句通常用逗号与主句隔开,常由 which、who、whose 等关系代词引导。
/nɒn rɪˈstrɪktɪv klɔːz/
My brother, who lives in London, is a doctor.
我哥哥住在伦敦,他是一名医生。
The Great Wall, which was built over many centuries, attracts millions of tourists every year.
长城历经数百年修建而成,每年吸引数百万游客前来参观。
Non-restrictive 由前缀 non-(表示"非、不")和 restrictive(限制性的)组成。Restrictive 源自拉丁语 restrictus,是动词 restringere 的过去分词,意为"束缚、限制"。Clause 源自古法语 clause,最终追溯至拉丁语 clausa,意为"结束、结尾",后引申为"条款、从句"。整个术语字面意思即"非限制性的从句",表示该从句不对先行词的范围进行限定,而是补充说明额外信息。
在简·奥斯汀的 Pride and Prejudice 中,大量使用非限制性从句来补充描写人物或场景细节,例如:"Mr. Darcy, who had at first scarcely allowed her to be pretty, was forced to acknowledge her figure to be light and pleasing."
查尔斯·狄更斯在 Great Expectations 中也频繁运用非限制性从句丰富叙事层次,例如:"Joe, who had ventured into the kitchen after me, drew a chair and sat down."