The context is the backcloth on which the values in planning are produced.

核心价值是生成规划合法权威的法理基础，但在制度环境中发生异化。

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Its vast acres of sloping greenery, its glades and its trees present a striking backcloth.

ECONOMIST: Henry Moore's outdoor sculptures

This would be an unpropitious backcloth to a decision to join the euro.

ECONOMIST: House prices

Even avowed republicans were taking part, perhaps seeing the Union flag trimmings as simply the backcloth to a party, like fairy lights at Christmas.

BBC: Diary of a street party, part 3