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to bend; to turn up; to turn down; to double
板を少し折り曲げた。
I bent the board slightly.
紙を折り曲げて立体的な形を作っていた。
I was bending paper to make a three-dimensional shape.
正確な角度で素材を折り曲げるには専用の道具がいる。
Specialized tools are needed to bend material at an exact angle.