Definition
to provisionally schedule an event or an engagement on a specific date, with the understanding that it might be adjusted in the future.
初步安排；暂时定下
I've penciled the meeting in for next Monday, but I'll adjust it once everyone confirms.
我暂时将会议安排在周一，但等大家确认后会再调整。
He suggested we pencil in the date for the cocktail party on Friday, knowing it can be changed at any time.
他建议我们暂时将鸡尾酒会的日期定在周五，因为随时可以更改。
Let me just pencil in this trip on the calendar for now, and we'll finalize the details later.
我先将这次旅行暂时记在日历上，之后再确定细节。