We say Pardon? When we did not hear what someone said and want them to repeat it.

若未听见某人刚说的话而请其重复时，说对不起？

youdao

Their English is a lot better and you will feel shamed if you always say pardon because they will speak in Chinese with you.

他们的英语口语都非常好，所以会用英语直接和你对话而不是汉语，如果你总是说“请再重复一遍”，自己会感觉羞愧。

youdao

If I break wind at dinner, should I say "Pardon," or pretend nothing has happened?

如果我在用餐的时候放屁，我是应该说“对不起”，还是假装什么事情都没发生？

《柯林斯英汉双解大词典》

If my code is correct, what should the average price be, after say, 100 days, if there's no bias. Pardon?

如果我的代码没写错的话，如果没有偏向值那平均价格会是多少呢，如果没有偏向值，请说？

麻省理工公开课 - 计算机科学及编程导论课程节选

Many activists say they expect Mr. Shafiq to pardon Mr. Mubarak if the ex-president's conviction is upheld.

WSJ: Candidates Jostle Over Mubarak Verdict

But a different, friendlier president might pardon Mr Nastase, whose supporters say the whole case was trumped up.

ECONOMIST: Romania in trouble