Question

【题目】__________ you promise to buy her a gift, you can’t break it in any case.

A. Once B. Until C. For D. That

Answer 1

【答案】A

【解析】句意：一旦你答应要给她买个礼物，那么你在任何情况下都不能失信。once＂一旦＂，符合语境。