1、 For instance, three keywords, "Beijing," "space shuttle," and "iguana," are used.
例如，使用 3 个关键字 “Beijing”、“space shuttle” 和 “iguana”。
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2、 Most keywords have an index that shows how lexical items and their related terms are organized.
大多数关键字都有一个索引，显示词汇项及其相关术语是如何组织的。
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