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putting one's hands behind one's back; having one's hands behind one's back
behind; rear; back
容疑者は後ろ手に縛られていた。
The suspect had their hands tied behind their back.
後ろ手を組んで廊下を歩いていた。
He walked down the hallway with his hands clasped behind his back.
校長先生が後ろ手を組みながら校庭を見回った。
The principal surveyed the schoolyard with hands clasped behind their back.