【正确答案】 Dear Laura,
I have to recall my invitation for the birthday tea party on Saturday afternoon.
I just heard that my grandmother is seriously ill. I must go to see her and I am leaving early tomorrow morning.
I am really sorry about that. I have been longing for holding such a party, and I know that you have been prepared to come and meet my family. So I will plan on a later date for the party. Sorry for this last minute change and I am sure you will understand my anxiety.
Truly yours,
Li Ming

【答案解析】这是一则取消邀请的便条，为避免对方误会，一定要解释清楚取消邀请的原因，言辞要诚恳。
第一段说明要取消之前的邀请。
第二段说清楚取消邀请的原因。
第三段诚恳道歉，并说明接下来的补偿做法。