Singular or plural question!

[Sioned11]

Which one is correct, please?

These are significant problems for a vast majority of university entrants, regardless of their nationality or first language.

OR

These are significant problems for a vast majority of university entrants, regardless of their nationalities or first languages.

I favour the former (something to do with a mass noun - but I can't quite put my finger on it). Or might they, possibly, be interchangeable?

Many thanks - this is bugging me!

The first one, I think. The second one sounds like each individual entrant may have more than one nationality or first language.

If I were to write this, I would say:

There are significant problems for the vast majority of university entrants, regardless of nationality or first language.

By definition there is only one majority, which makes me think the definite article should be used.
The second clause just reads better in my head without the article. I'm sure they should also be singular because most would only have one nationality and first language.

Yep - nationality and language agree with majority I believe.

First one as well. And I'd stick the word "individual" after "their" to make it clearer.

First sentence, except that it should be "These are significant problems for the vast majority of university entrants".

Many thanks, all. especially for such speedy responses. Some excellent points - from a definite article for 'majority' to popping in 'individual' after 'their'.

It's one thing to have an instinct, it's another to understand. So, thank you again.