訓 まも(る) ・ 音 シュ,ス
Sino-Vietnamese: thủ
宀 (roof) over 寸 (a hand): a hand standing guard inside the house. To protect, to defend — and also to keep a promise or a rule.
Stroke data: KanjiVG (CC BY-SA 3.0) — kanjivg.tagaini.net
約束を守ってください。 (やくそくをまもってください)
Please keep your promise.