求：谢绝邀请信，具体内容如下

你被邀请去参加一个宴会，但是你要工作，写一封谢绝信，字数要求120字以上！

Dear...,
Thank you very much for inviting me to the party. I do appreciate your invitation, but I'm afraid that I have to work that day. So it's impossible for me to attend the party. I'm grateful to your invitation and I am looking forward to having another opportunity next time.
Best wishes,
...

dear principle, the foreign language department is about to held a talent competition.we sincerely hope that you could attand this event, which is surely a great honour to us. thank you and looking forward to your reply. the students' union of foreign language department