- 你一旦了解她，就喜欢她了。
You'll like her once you get to know her.
- 他一旦下了决心就毫不动摇[无法使他改变（意见）]。
Once he's made up his mind, he never budges/you can never budge him (from his opinion).
- 一旦你掌握了煎蛋饼的技巧，做起来就很容易了。
Making an omelette is easy once you've got the knack (of it).
- 那盗贼下决心，一旦获释便重新做人。
The thief was determined to turn over a new leaf once he was released from prison.
- 政治家在选举前空口许愿，一旦上台就根本不是那麽回事了。
Politicians promise the earth before an election, but things are different once they are in power.
- 一旦下了决心，他就毫不动摇。
Once he's made up his mind, he never budges.
- 一旦开始，就必须继续。
Once you begin, you must continue.
- 他一旦宣了誓，他就一直忠贞不渝。
Once he took the vow his loyalty never wavered.
