词汇优化：

参赛者：participant contestant参与：participation学生办公室：the student association office比赛：contest competition精彩的：fascinating awesome wonderful增进：enrich enhancewill be hosted inwith Chinese featuresset off on timedeep-rooted culturesome significant worldwide achievementThe most fascinating arrangementswon a award

起始段

1.I am glad to invite you to participate in…

优化：

It's a great privilege(荣幸) for me to invite you to participate in…I,on behalf（我代表）of the Robotic Hobby Group,intend(想要) to invite you…

2.There will be an exhibition in our school

优化：

I am writing to tell you that our school has scheduled （正准备）a contest of

3.I know you are interested in…

优化：

Knowing you have a keen interest inBeing fully aware of your keen interest in

中间段

1.Your performance will not fail to impress the audience(观众)

优化：

Your fluent Chinese,excellent public skills,and especially profound(深远的)knowledge will not fail to impress and inspire the audience.

2.The show will be held after three days,and it will be last three days,it aims to promote our knowledge.

优化：

The show,meant to promote our awareness(认识)of our history,will take place three days away on July 5th,lasting a whole week.