Ci deve essere qualcosa che non va.
(There must be something wrong)
Frase originale: I ... I
spagnolo: Yo ... el
inglese: I ... he
francese: Je ... il
2' inglese: He ... I

That's why I tagged Spanish sentence as "ambiguous", because in Spanish it is

Yo creía
Tú creías
Él creía

Yo era
Tú eras
Él era

So "creía que era" may mean "I thought I was", "I thought he was", "he thought he was", "she thought he was", "he thought she was", "he thought I was"...

What does this sentence actually mean? Is it a kind of idiom?

I guess, it might be said by a person with a personality disorder. Is there possible any other explanation?

I was > he was

actually it is a matching translation of the Spanish sentence, although it is quite unlikely, at that time I thought it was a good idea to show all the possible translations of the Spanish sentences, no matter how unlikely they were; but if you think it should be changed to "I thought it was my brother" (a more likely sentence and still another possible translation of the Spanish sentence), I will do it.

This sentence should be " I thought he was my brother" Please change it or delete.

Ok, I changed it.

Why can't people stand that you thought you were your brother, I wonder?

I wonder the same thing :P but the majority has spoken, and Tatoeba is a democracy most of the time :P

Thanks:)

> I thought it was my brother.

This seems strange to me, too.