And the statistics of 33 species of birds, by means of meeting frequency index, show that there are 5 dominant species, 8 common species and 20 rare species.

并对33种鸟采用遇见频次指数法进行数量统计，其中优势种5种，常见种8种，稀有种20种。

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Your data and the text index need to be explicitly synchronized if no update frequency is specified.

如果没有指定更新频率，那么需要显式地对数据和文本索引进行同步。

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The create index command establishes the text index infrastructure by defining the text index attributes, such as update frequency, a document format, an index directory, and so on.

create index命令定义文本索引属性，比如更新频率、文档格式、索引目录等等，从而建立文本索引基础设施。

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An index of 1.00 means that the frequency of failures is matched to its percentage of vehicles on the road, and thus, has average reliability.

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