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to gather (of people); to assemble; to hang out
to assemble (of troops); to be stationed; to be quartered
若者が公園に屯した。
Young people gathered in the park.
夜遅くまで若者たちが路地に屯していた。
Young people were hanging around in the alley until late at night.
繁華街で若者が屯するのを防ぐための対策が講じられた。
Measures were taken to prevent young people from loitering in the busy district.