这句话应该要插入逗号吗？

这两天在给学生们讲到《新概念英语》经典版第二册第43课时，突然想到文中有句话好像值得商榷。先来看看原文：

In 1929, three years after his flight over the North Pole, the American explorer, R. E. Byrd, successfully flew over the South Pole for the first time. Though, at first, Byrd and his men were able to take a great many photographs of the mountains that lay below, they soon ran into serious trouble. At one point, it seemed certain that their plane would crash. It could only get over the mountains if it rose to 10,000 feet. Byrd at once ordered his men to throw out two heavy food sacks. The plane was then able to rise and it cleared the mountains by 400 feet. Byrd now knew that he would be able to reach the South Pole which was 300 miles away, for there were no more mountains in sight. The aircraft was able to fly over the endless white plains without difficulty.

文中红体标示出来的这句话，从结构上来讲，是一个较为复杂的并列复合句：第一层关系为由for引导的对前文的原因作补充说明的并列句“for there were no more mountains in sight”，第二层关系为由that引导的宾语从句“that he would be able to reach the South Pole which was 300 miles away”，第三层关系为第二层关系中由that引导的宾语从句中包含的由which引导的定语从句“which was 300 miles away”。

小编学习这套教材已经有十几年的时间，但却一直没有发现这句话中的蹊跷。最近因为一直在分享《新概念英语》语法的内容，其中就分享了有关定语从句的内容，所以这两天给孩子们讲到这篇文章时，脑子里突然就蹦出了这么个想法——这个句子是不是应该在Pole和which中间插入一个逗号？

为什么要插入一个逗号？这就得从定语从句（大家可点开前面红体的文字链接，查阅小编分享的有关定语从句的内容）的分类讲起了。英语里，按照从句与先行词的关系，可分为限定性定语从句和非限定性定语从句：限定性定语从句主要对先行词起着修饰限定作用，往往具有特指功能，是整个句子不可或缺的成分；非限定性定语从句主要对先行词起着补充说明作用，往往用逗号与主句隔开，即便是省略了这个从句也不会对整个句子的大意造成大的影响。

因此，如果原文中的which不是因为出版社的刊印失误，那which引导的就是个限定性定语从句，原文中的“the South Pole which was 300 miles away”意思就是“300英里之外的南极”。但是，南极（the South Pole）是个专有名词，而且具有唯一性，所以这种情况肯定要用非限定性定语从句来修饰，否则原文的潜台词就是：世界上还有其他南极，比如500英里之外的南极，而不仅仅是300英里之外的南极。

综上，小编以为还是在Pole和which之间插入一个逗号为好。这样，在不影响整句话的通顺表达的前提下，which引导的定语从句可用小括号中的补充说明方式来翻译，由此原文中的整个句子就可以改为“Byrd now knew that he would be able to reach the South Pole, which was 300 miles away, for there were no more mountains in sight.”，译文可作此处理：Byrd现在清楚，他肯定能够设法到达南极了（距离300英里之外），因为前方视线所及已经没有任何高山阻挡了。

当然，原文作者之所以没有加这个逗号，也可能是因为结构上受后面for引导的并列分句的影响，毕竟which引导的从句只是与Pole相关，逗号隔开之后会显结构上松散。但是，作为定语从句，限定性与非限定性之间毕竟存在原则上的差异，所以小编还是认为应该加上逗号。

以上只是小编的个人理解，有点“无知小样挑战权威大咖之嫌”；因个人见识所限，也许是曲解了原文的意思，欢迎大家拍砖指正！

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