Dear Jane,
I am excessively sorry to tell you that I won’t be able to come this afternoon because I have to go to the airport at 2:00 p.m. to meet an overseas visitor Australia.
I really have kept our date in my mind all these days. However, I received my boss’e-mail this morning, and he asked me to go to the airport to meet one of his fris abroad. It’s sudden and urgent and I must go.
I’m sorry for any inconvenience caused. Please forgive me. Would you please ring me up to make another time? We may meet again and I hope to see you soon.
Sincerely，
Li Ming