be a matter of principleto be something that you feel you must or must not do, because of your moral principles 是原则问题 She couldn’t take the money. It was a matter of principle. 她不能拿这笔钱，这是原则问题。
be a matter of principle• Dessert is a matter of principle here.• It was a matter of principle.• First, there are matters of principle.• They might have gone higher but this is a matter of principle.• It seemed, as much as anything, to be a matter of principle.
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