pledge in all sincerity and seriousness vow solemnly take an oath devoutly give sb. one´s firm and solemn promise
They had given an absolute assurance that it would be kept secret.
他们信誓旦旦地保证将对此绝对保密。
—— 柯林斯例句In 1990, we were all earnestly assured that property values could only go up.
1990年时我们都得到信誓旦旦的保证说房地产只可能升值。
—— 柯林斯例句Yuan Shih - Kai once promised to uphold Republican principles.
袁世凯曾经信誓旦旦,说要坚持共和原则。
—— 辞典例句Meg was much flattered by Mr. Ned´s assurances that he came especially to see her.
尼特先生信誓旦旦地告诉麦格,他是专门为她而来的。 麦格听了真是受宠若惊。
—— 辞典例句There were novelists of the time, like Howells, who avowed that they were " realists ".
当时的小说家如 豪威尔斯 等人,都信誓旦旦地自称是现实派。
—— 辞典例句