英语生日邀请函写法如下：

1、英文邀请函格式首先可以表明活动的主题、时间以及地点等；

2、其次可以写参加活动的主要人员；

3、然后可以写此活动的具体内容以及注意事项;

4、最后结尾部分可以写希望接受邀请并准时参加活动。

Dearsir/madam:

I'mdelightedyouhaveacceptedour invitationtospeakattheConferencein city

on date.

Asweagreed,you'llbespeakingonthetopic from time to time.

Therewillbeanadditionalminutesforquestions.

Wouldyoupleasetellmewhatkindof audio-visualequipmentyou'llneed.

Ifyou couldletmeknowyourspecificrequirements by date.

I'llhaveplentyoftimetomake surethatthehotelprovidesyouwithwhat youneed.

Thankyouagainforagreeingtospeak.I lookforwardtohearingfromyou.