I am back to the classic 当 vs。 是。 I've heard some people say “这个词也可以是动词” however could I also say "这个词 也可以当动词“ － if so, which sounds more common/colloquial?
Both words are common and can be used colloquially. In formal/academic context, I'd replace
If the word is not verb but can be used as a verb, you should say 当, e.g.
If the word is a verb, you should say 是, e.g.