私(わたし) watashiは wa転(ころ)ん()だ() koronda瞬(しゅん)間(かん) shunkanに ni手(て)首(くび) tekubiを o折(お)っ()た() ottaこと kotoが ga分(わ)か()っ()た() wakatta。 I knew the moment I fell that I had broken my wrist. accidents~瞬間に (at the moment of)~ことが分かる (it becomes clear that)