The bank has agreed to give an immediate refund in the unlikely event of an error being made.

银行已同意倘若出现不太可能的错误便立即退款。

《柯林斯英汉双解大词典》

Q: In the unlikely event of a true disaster, what is most important?

问：在不可能出现的真正灾难中，什么最重要？

youdao

In the unlikely event you need it, excellent medical care is available.MEMORABLE CONCLUDING REMARKS

Ⅲ.即使你生病，优质的医务随时提供。 5.印象深刻的结尾

youdao

Even in the unlikely event that the government had some extra money to spend.

BBC: Should we forget about growth?

In the unlikely event that Congress does act responsibly to restore fiscal prudence, its AAA would be validated.

FORBES: S&P Downgrade Of U.S. Debt Says Nothing New

The White House has promised to veto the measure in the unlikely event that the Democratic-led Senate approves it.

NPR: House Passes Bill To Prioritize US Debt Payments