break a promise (bureiku a puromisu)

Idiom Promise

意味

to fail to do what one promised

約束を破る (yakusoku o yaburu)

例文

"She broke her promise and didn’t call him."

"彼女は約束を破り、彼に電話しませんでした。" (kanojo wa yakusoku o yaburi, kare ni denwa shimasen deshita)