I think both are acceptable as both 'at a meeting' and 'in a meeting' are acceptable according to Longman, but I am not a teacher.
Student or Learner
Which preposition should be used with the noun "concert" when we want to say either that we attend it or that someone performs in the concert?
-Sarah is going to play the electric guitar in/at the concert.
-Where are you? I am at/in a concert.
-He was sitting next to me at/in the concert.
I believe that both prepositions are acceptable, but I do not know if both can be used in all contexts and if the choice of one of them somehow affects the meaning.
I would use "at" for spectators and "in" for performers. To me "in a concert" has the specific meaning of performing in a concert.
E.g. "Tomorrow I will be in a concert." = "Tomorrow I will be performing in a concert.".
"Tomorrow I will be at a concert." = "Tomorrow I will be attending a concert.".
The difference between a concert and a meeting is that everyone attending a meeting will be taking part, and so at various points they may either be speakers (essentially performers), or spectators. At a concert people are either one or the other.
Last edited by Eckaslike; 18-Aug-2015 at 09:03.
(BrE first language speaker.)
Thank you very much!
That was my idea, too, though I was not sure. That's why I firstly typed 'in' the 1st sentence and 'at' in the 2nd and 3rd (though these two can be interpreted in two ways) as my suggestion.