Is this an 2 choice of just one
There are more than one words that could fit here
Club - Self-describing, it's the same in spanish
"a la discoteca" - Discoteca is that, a disco, a place for dancing and listening to music
Concierto - A concert
I could probably think of more, but I guess you have enough there. Choose the one you like best
un - masculine singular
una -feminine singular
unos - masculine plural
unas - feminine plural
UN lápiz - a pencil
UNAS tareas - some homework
UNOS borradores - some erasers
UNAS mochilas - some backpacks
UNOS libros - some books
UNA calculadora - a calculator
UNOS papeles - some papers
UN examen - a test
Many times we can find the right article by paying attention to the noun ending:
unAS tareAS
unOS librOS