The supplier requires an irrevocable letter of credit before shipping the goods overseas.

供應商要求在貨物運往海外前先開立不可撤銷信用狀。

Once you click submit, your hotel booking becomes irrevocable and no refund is available.

一旦按下送出，您的飯店訂房即無法撤銷，也不予退款。

The board's irrevocable decision to close the branch surprised many long-time employees.

董事會關閉分行的不可撤銷決定，讓許多資深員工感到意外。