Usage priority
Collins 词频等级为 1，建议结合例句记忆，而不是只背中文释义。
备用、储备或额外
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备用、储备或额外；作为备份的；支持、加强；(音乐)与伴奏相关的；候补的；支持的；[计] 备份; DOS外部命令:通常使用于将硬磁盘上指定的文件复制到软盘上
Standby, reserve or extra.
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备用、储备或额外
Standby, reserve or extra.
作为备份的
That is intended as a backup.
支持、加强；(音乐)与伴奏相关的
Supporting, reinforcing; (music) of or related to accompaniment
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Includes Context & register & Memory tip
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Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
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Collins 词频等级为 1，建议结合例句记忆，而不是只背中文释义。
页面下方列出了常见词形变化。学习时注意它们在句子中的语法位置。
Dictionary facts from DICTIONARY_API_DEV, ECDICT, WIKTIONARY.