护照号护照具有由护照颁发机构分配的数字或字母数字表示(“系列号”)。

Passport number Passports have numerical or alphanumerical designators (" serial number ") assigned by the passport issuing authority.

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图6崂山湾不同区域不同月份游泳动物群落nmds排序分析。数字表示月份，字母表示区域。

Fig. 6 NMDS analysis of the nekton community in different months and different zones in Laoshan Bay. Digits indicate the month, and letters indicate zones.

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上学后抽象思维的能力显得十分重要，比如用数字表示一系列物体和用字母来表示语音等等。

This skill is important in school where a child will have to learn that numerals symbolize grou. p. s of objects, letters symbolize sounds, and so on.

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