訓 はら ・ 音 ゲン
Sino-Vietnamese: nguyên
厂 (a cliff) sheltering a reduced 泉 (spring): water welling out at the foot of the rock. The source, the original — and also an open plain.
Stroke data: KanjiVG (CC BY-SA 3.0) — kanjivg.tagaini.net
事故の原因を調べています。 (じこのげんいんをしらべています)
They are investigating the cause of the accident.