当有客人来的时候，我们常常说"欢迎"，表示很高兴见到他。

When guests arrive, we often say "欢迎" to express that we are glad to see them.

这个词也可以用来请别人做某件事，比如"欢迎大家来参加"。

This word can also be used to invite others to do something, like "欢迎大家来参加" (Welcome everyone to join).