language是语言的意思。而spoken则是说的意思,区别可以从以下例子看出:

I don't understand what language he has spoken, even he speaks in English, but I am still confused, maybe I ask him write down what he wants. 我不明白他说的是什么语言,即使他说的是英语,但我仍然很困惑,也许我让他写下他想要什么。