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guard; sentinel; garrison
宮殿の前に衛兵が整然と立っていた。
Guards stood in orderly formation in front of the palace.
衛兵の交代式は観光客に人気がある。
The changing of the guard ceremony is popular with tourists.
衛兵が不審者を発見し直ちに通報した。
The guard spotted a suspicious person and reported it immediately.