尽管自然语言的关键词标引和规范语言的主题词标引都被用于揭示和查询同一主题的档案，但它们实现的方式却不相同。所以没有严格的限制条件而随意判定哪一个更好，是不现实的。谁个优，谁个劣完全取决于系统需求的平衡。对这个“平衡”议论较多的一种说法是 “背着抱着一样沉” Although both natural language keyword indexing and canonical language keyword indexing are used to reveal and query files on the same topic, they do so in different ways. Therefore, it is unrealistic to judge which one is better without strict restrictions. Who is superior, who is a bad one depends entirely on the balance of system requirements. One of the more talkative arguments about this “balance” is “carrying and hugging the same”