tool book的用法和樣例：
例句
- The reference book is indexed in alphabetic order.
這部工具書是按照音序編製索引的。 - Sure, you could just leave this on your shelf as a dusty reference tool, picking it up only on those occasions when you encounter an unknown term or acronym.
當然，你也可以將本詞典作為一本放在書櫃里的塵封工具書，只有在遇到不懂的術語或縮略語時才偶然拾起。
