Definition
To inform someone in advance about something that is about to happen, usually to allow them to prepare.
事先通知
I just wanted to give you a heads up that next week's meeting has been moved to Wednesday.
我只是想提醒你，下週的會議已經改到星期三了。
He gave me a heads up that the boss is not in a good mood today.
他提醒我今天老闆心情不好。
We should give our clients a heads up about the system maintenance.
我們應該提前通知客戶關於系統維護的事。