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to come apart at the seams; to be ripped; to be torn
to begin to open; to begin to bloom
to smile broadly; to break into a smile
古いコートの縫い目が綻びてきた。
The seams of the old coat are coming apart.
計画の綻びが徐々に明らかになった。
The flaws in the plan gradually became apparent.
縫い目が綻びれば直ちに縫い直すようにしている。
If a seam comes apart, I make a point of resewing it right away.