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

我暗暗发誓今后要更加小心。

I took my marriage vows and kept them.

我结婚时许下誓言，并一直信守。

While many models vow to go back to college, few do.

很多模特儿发誓要重返大学校园，但几乎无人做到。

I solemnly vowed that someday I would return to live in Europe.

我郑重起誓总有一天我要重回欧洲生活。