I made a silent vow to be more careful in the future.

我默默发誓今后要更加小心。

《柯林斯英汉双解大词典》

Vow to be a flower bearing fragrance.

发愿作一朵鲜花，吐露芬芳，给人清香。

youdao

Vow to be a streetlight showing the way.

发愿作一盏路灯，照破黑暗，指引光明。

youdao

You have a freewill offering--just because someone wants to do this, a freewill offering. And you have a vow offering that would be offered on the successful completion of a vow, for example. And these sacrifices are all entirely optional.

自由祭品--只因为有人想这么干，自由祭品，还有一个誓言祭品,举个例子，一个誓言如果成功达成，便会供奉祭品，这些祭品都是可选择的。

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Members vow to be generous where once they had been selfish, faithful where treacherous, honest where deceitful.

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Why is that the position that this administration would take, given that you vow to be the most transparent in history?

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When I started having kids, I made a vow to be a father with energy -- you've got to be responsible for you health.

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