意思就是说要您为请柬上的日子留出时间,在那天要按时出席,不要因给其它事情耽误了.
以下是我在国外网站上找到的解释：
A save the date notice is an item stating the date of a wedding or other formal event. It typically states the date when a couple plans to marry, so that recipients will know to keep that date free. Save the dates usually take the form of a card, but can also be a refrigerator magnet or similar item. They are sent out at least six months before the wedding date, and are usually followed by a formal wedding invitation.