nice to meet you 请问 里面的to 是什么词 还有 happy birthday to you 中的 to 是什么词

Nice to meet you! Nice to meet you . Nice to meet you nice to meet you, nice to meet you .同义词 ( ）( )nice to meet you Nice to meet you.Nice to meet you,too. Nice to meet you,too hello,nice to meet you! nice to meet you,Mr HELLO,NICE TO MEET YOU. nice to meet you ,too to you Nice meet too haha,nice to meet you 请问nice to meet you 和 nice meeting you 的区别, nice to meet you等于nice to什么younice to meet you.同义词nice to Nice to meet you.Nice to know you. Nice to meet you.Nice to know you. 请问英语中的nice to see you和nice to meet you有什么不同?如何使用和区分?