A question about 'su' and sus'

Question

In this sentence would i use 'su' or 'sus'? Maybe i can use either?

Beth y Josh celebran su cumpleaños

I always thought it would be 'sus' but somebody told me not. Help, little confused

Answer 1

A birthday is one thing (El cumpleaños).

Here it appears there are two birthdays being celebrated, so sus should be used.

I agree, it just took me a while to get there! :) - 0066c384, Jan 11, 2011

Well I don't agree, see my post. - kenwilliams, Jan 11, 2011

Answer 2

It is one birthday that they both share Su cumpleaños and not sus cumpleaños.

Ken, even twins have their own birthdays. It is possible that just one birthday is being celebrated, but then it must be "Josh y Beth celbran el cumpleaños de (somebody)" without a personal pronoun unless prior context is given, which it isn´t here - 005faa61, Jan 11, 2011

Answer 3

The problem I see is that "cumpleaños" can be either plural or singular. If written in English, this would be "Beth and Josh celebrate their birthday(s)", so the plural is not a problem in this sentence.

If I were to construct this sentence prior to this question, I would have said "sus" because I am still trying to translate from English to Spanish. If you run the sentence through the translator engines on this site, you get both "su" and "sus".

I'm going with "sus" on this one, even though the dicitonary says "su" can mean "their". I don't know if "cumpleaños" is singular or plural in this sentence, but if multiple birthdays are involved it should be "sus". To me, "Beth y Josh" implies multiple birthdays.

Answer 4

It must agree with the object, which is "cumpleaños." Cumpleaños is singular, although it may appear plural.

Or it is plural which is indistinguishable from the singular, absent context. - samdie, Jan 11, 2011

Answer 5

I can see why you're confused.