It's happy to see you again.为什么中间要加to?不加不行吗

It's happy to see you again.为什么中间要加to?不加不行吗 nancy it's happy to see you ,to. It’s glad to see you again句子成分分析 Matt is happy to see his sister again see前面问什么要加to啊 it's glad ＿＿ you again . a.see b.to see c.sees选什么为什么? How ( )it is to see you again How____ it is to see you again! A. happy B. please C. glad D It\'s nice to see you again.Have you changed jobs? .―It's nice to see you again.Have you changed jobs?―No,my co It's nice to meet you again I can't say___I want to see you again.It's two years since I 9.Good to see you again.It”s almost three years___we met las