A motto or quotation, as at the beginning of a literary composition, setting forth a theme.

引语，格言在一部文学作品开头的引言，警句，阐明主题。

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Because China does not disclose the composition of the basket, setting the value of the yuan in this way provides its currency managers with a high degree of flexibility.

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Instead of re-contextualizing it on your instrument in music as part of your own composition, you could then re-contextualize the piece by taking the actual piece and putting it in a new setting.

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