specifing to whom or what?

Question

Hi I'm trying to learn Spanish and I came across a sentence which caused my learning app and my native Spanish speaking partner to disagree:

The original sentence from the learning app: "Si puede, deles una explicacion a sus alumnos"

My partner say it's wrong, and it should be "Si puede, dele una explicacion a sus alumnos"

Since it refers to giving an explanation which is singular and not plural.

To my understanding, it should be plural because it's given to the students.

Which one is the right one??

Thanks!

Accepted Answer

Hola Amit
It is grammatically correct with "deles" because here, "les" is an indirect object pronoun that is referring to the plural "a sus alumnos". 
It is nevertheless a common use and you will hear it quite often with a singular pronoun "le" even though when it should be plural. But if we are talking about being accuracy in grammar, you need "les".
Other examples where you may hear/read "le" instead of the correct "les" could be for example:
"No le(s) pongas mostaza a las hamburguesas."
Don't put any mustard to (on) the burgers.
"Ella le(s) dijo a los invitados que tenían que llevar corbata."
She told the guests that they had to wear a tie.
Here is some information about this "non-recommended" use of le. Have a look.
Saludos
Inma

Answer

Very helpful reply. My first rate tutor, from northern Spain, frequently responds to my questions about choosing between grammaticaly correct but quite distinct alternatives in terms of which is more commonly used in speech or in writing (or in literary forms or coloquial forms). The problem of translating the english passive seems an interesting one as the se-passiva appears to be the standard spoken useage while the passive with ser is more normal in writing. Then there is the distinct por problem about agency. I suppose RAE defines correct for Spanish albeit Molinar is much richer. How anyone can define correct in English is surely just a matter of social class?