I am happy to join with you today in what will go down in historyas the greatest demonstration for freedom in the history of our nation.如何翻译呀?谁来分析一下这个句子?这里的 what will go down是什么东东?～～

i am happy to join you I'm new here.And it's very happy for me to join the big family ,I am honored to be your student.I'm new hereAnd it's very happy for me to join the big family ,I am honored to be your student.I want to say I will follow you to improve my English.In fa I have a dream by Martin Luther King, Jr. I am happy to join with you today in what will go down in翻译一下 I am very happy to have you! I am very happy to work here I am happy to be with you I am happy to share with i am so happy to learn I am happy to be invited.why i am so happy to learn I am happy to have 、急 I am happy to help you.I am ( ) ( )help you. I am very glad to join in this class. 语法分析：I am happy to join with you today in what will .I am happy to join with you today in what will go down in history as the greatest demonstration for freedom in the history of our nation.请帮助分析一下句子结构,what 是指什 i am very happy to have chance to be I am happy! I am so happy I am so happy.