子こども子こどもする

expression, suru verb (irregular)

be very childlike; be very childish

Describes behavior, appearance, or attitude that is strongly reminiscent of a child, often with a negative or critical nuance when 'childish' is meant. Used as a する verb phrase.

• 彼かれの言いい訳わけは子こども子こどもしていて、聞きくに堪たえない。

  His excuses are so childish that I can't stand listening to them.

• その服ふくは子こども子こどもしすぎて、大人おとなには似に合あわない。

  Those clothes are too childlike and don't suit an adult.