口(くち)を揃(そろ)える

くちをそろえる
expression
to say the same thing; to say in unison
idiomcommunication
1. to say the same thing; to agree unanimously; to say in unison
Of several people: to say the same thing, either all at once or each separately when asked.
みんなが口(くち)を揃(そろ)えて「はい」と言(い)った。
Everyone said "yes" in unison.
The guests all praised the food.
Everyone who knew him says the same thing: he was earnest and kind.

Usage

Almost always in the て-form before a verb of saying: 口(くち)を揃(そろ)えて言(い)う / 褒(ほ)める / 反対(はんたい)する. Common in news reports quoting several witnesses or experts who agree.

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