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flat; level; even; smooth
calm; tranquil; placid; composed; stable
relaxed (sitting posture); comfortable
plateau; tableland; plain
この道は平らなので、歩きやすいです。
This road is flat, so it's easy to walk on.
机の上を平らにしてください。
Please make the top of the desk flat.
公園の平らな場所でピクニックをした。
We had a picnic in the flat area of the park.