We need at least 24 hours' notice of cancellation.

如欲取消，请至少提前24小时告知。

《牛津高阶英汉双解词典》

You must give at least 24 hours'notice of cancellation.

如要取消,必须提前24小时通知.

互联网

You must give at least 24 hours'notice of cancellation.

如要取消,必须提前24小时通知.

互联网

You must give at least 24 hours notice of cancellation.

如要取消,必须提前□□小时通知.

互联网

Notice of cancellation of reservation shall reach the Office bye - mail the soonest possible.

如欲取消订房,应以电邮形式尽快通知房屋事务处.

互联网