ETS/GRE's definition of a ring/sub-ring.

[Legendre]

Do we need a multiplicative identity?

[PNT]

It's fairly standard for rings these days to require multiplicative identity, but I expect there will be no ambiguity in that questions will explicitly state "Rings with unity/identity". I certainly don't expect there to be questions on Rings without identity but I could be wrong.

[Legendre]

Thanks. I suppose so.

I guess the most common requirement of subring questions: the subring test, isn't affected by this. Since we just need to check for unity, which hopefully will be given.