"You and I are friends."
Translation:Tú y yo somos amigos.
I used "amigas" just to force the issue, and it rejected it. Reported 11 March 2018.
A form of ser is used here because the predicate object (the thing to the right of the verb) is a noun. If you have a noun object, you use ser. Estar only takes adjectives (unless it's part of a verbal construction, of course).
Somos is the nosotros conjugation of ser. It means "we are" and is used when you're talking about a group that includes the speaker ("we").
Son is the ellos/ellas and ustedes form of ser, so it translates as "they are" or "you are". It's used when you're talking to a group ("you", plural), or about a group that doesn't include the speaker or the listener ("they").
If talking about girls who are friends its amigas, if talking about boys who are friends its amigos but if they don't let you know if they are boys/girls then it's not possible to do it right the first time! I agree with you!
We need to learn all the possible translations. And Duolingo needs to provide them. I am not talking about the many ways stuff can be said in English here.
There is no reason why Duolingo shoukd let us know whether the answer should be amigo or amiga. Either should always work. And if either does not then both aren't in the database as correct answers. And whichever isn't needs to be reported so it can be included.
...and if you are a male and your friend is a female, do you use "amigos"?
Yes. Call it what you will, but in Romance languages, a group is feminine only if it is exclusively comprised of women. If a single man is included, it is masculine. At minimum, this is the case for Spanish and French, but this may also be out of date as it was a rule of thumb I learned in middle school French over a decade ago.
Not out of date as it is in English. I expect it will one day be out of date in English though.
Is “ustedes y yo son amigos” too much of a stretch? Thought I would try it but the owl hated my attempt.
You have to see who that resulting group consists of. Since the speaker is including themself in the group they're talking about, the resulting group will be a "we", so you have to use somos here. Basically, "You and I, we are friends."
Which exact translation of "you" you use here doesn't matter. It'll always be somos.
Ser is used in DOCTOR:
Description Origin Characteristics Time Occupation Relation
Hence, the use of somos vs estamos
Somos is the nosotros form, used when "we" are something. Son is the ellos/ellas and ustedes form, used when "they" or "you all" are something.