"He is someone else, not my boyfriend."
Translation:Li estas iu alia, ne koramiko mia.
Apparently "Li estas iu alia" is correct as well. I've never encountered "iu alia" in the lessons (I studied this section on my phone) -- maybe in te desktop version there's an explanation?
"alia" means "other." "iu" means someone. Someone other, someone else.
probably just to remind you that it can be that way round. It doesn't make any real difference.
I know this is an old question, but I see that it hasn't received a good answer. The sentence would actually be better as "mia koramiko". "Deactivated user" is not totally correct. Putting "mia" on the end for many speakers gives a meaning closer to "a boyfriend of mine" - which only makes sense for someone with multiple romantic involvement.
Where are you getting that from? Adjectives can go before or after nouns without changing the meaning. According to the PMEG, "mia" and the like are adjectives, specifically stating "Ankaŭ posedaj pronomoj[...] estas A-vortoj." and all adjectives can go before or after nouns, "Rekte priskribantaj A-vortoj staras plej ofte antaŭ la priskribata O-vorto, sed ili povas stari ankaŭ post ĝi. Eĉ povas esti A-vortoj samtempe antaŭ kaj post la sama O-vorto." http://bertilow.com/pmeg/gramatiko/a-vortoj/bazaj_reguloj.html and http://bertilow.com/pmeg/gramatiko/a-vortoj/uzo.html
I actually discussed this with Bertilo at NASK last summer.
"Mia" is not an adjective. It's a kind of pronoun. It's also a "difinilo."
What I discussed with Bertilo (and he agreed - although I don't mean to speak for him) is that difiniloj always come at the head of the noun phrase. When you move it to the end, it weakens the word's role as a difinilo.
So this (definite) - the boyfriend which is mine
becomes this (indefinite) - a boyfriend which is mine
I was careful in my post above to say that not all speakers recognize this difference, but it is very common, and I would expect the course authors to take it into account.
P.S. Note that Tuvalkin (see below) understood it the same way.
Interesting. Some other grammar guides, apart from the PMEG, even explicitly state that personal pronouns act the same as all other adjectives, and that the word order doesn't matter. For example, Esperanto Chicago's page here: http://www.esperanto-chicago.org/key.htm
If it is common, the course and other references should be updated to reflect that. As shown here, it can make a difference.
To be clear, PMEG actually says the following (in the link I provided above):
> Iuj provas uzi posedan pronomon kiel postpriskribon por montri nedifinan sencon: Amiko mia estas advokato. Tia uzo tamen ne estas ĝenerale akceptita, kaj ne ĉiuj komprenas, ke la nekutima vortordo celas montri nedifinan sencon. Normale oni do devas uzi iun el la pli klaraj esprimomanieroj montritaj ĉi-antaŭe.
The bottom line is that if you're intention is to use the definite expression "my boyfriend" - then mia should be up front so there's no doubt. If you want to use an indefinite expression (one of my boyfriends) PMEG advises to use something like "unu el miaj koramikoj" or "koramiko de mi."
I am of the school that would "koramiko mia" - well, if that's how my bread was buttered.
- Mia edzino - my wife
- Edzino mia - meaning potentially unclear - a wife of mine.