She swore blind she didn't know what had happened to the money.

swore 是动词 swear 的过去式，swear 的基本意思是"发誓、郑重承诺"，常带有强烈的情感色彩。 swear blind 是英语习语，字面意思是"像盲人一样发誓"，实际表示"非常肯定地发誓"或"信誓旦旦地保证"，强调说话者对自己所说内容的绝对确信。