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first place (in a race); first to arrive
one suit (of clothes); one item (of clothing)
putting on (formal clothes); wearing
one move
マラソンで一着になった。
I finished first in the marathon.
一着でゴールした瞬間が忘れられない。
I can't forget the moment I crossed the finish line first.
一着と二着の差はわずか一秒だった。
The difference between first and second place was only one second.