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to calm down; to compose oneself; to regain presence of mind; to relax
to calm down; to settle down; to die down; to become stable; to abate
to settle down (in a location, job, etc.); to settle in
to be settled (of an arrangement, conclusion, etc.); to be fixed; to have been reached
to harmonize with; to harmonise with; to match; to suit; to fit
to be unobtrusive; to be quiet; to be subdued
騒動が落ち付くまでしばらく待とう。
Let's wait a while until the commotion settles down.
新しい環境にようやく落ち付いてきた。
I have finally settled into the new environment.
深呼吸をして気持ちを落ち付けた。
I took a deep breath and calmed myself down.