同事们一起去吃午餐。 有必要同去吗？

他们都比我小致少五岁。情景是在一家大的会计师事务所。一些刚来得同事， 大概都和我同天开始工作。Some of them went out together for lunch. They didn't ask me since I have my own office but they are sharing the same office. But when I saw them go for lunch, I said I wanted to go together. 他们不是很欢迎我，because of ages and I am the only Chinese. Language is part of the reason also. Do I need to go with them in the future?

There are always a lot of small talks during the lunch time. That is why I think I should go. By the way, senior level personnels don't go with them.