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watch; guard; lookout; surveillance; watchman; sentinel
出口に見張りを立てた。
We posted a lookout at the exit.
夜間の見張りを交代で担った。
We took turns standing night watch.
工事現場の見張りを任されて夜通し警戒した。
I was put in charge of watching over the construction site and stayed alert through the night.