Hallo,
Sorry, i don't speak Dutch, and not many user active here...
So, the best way is to use Joomla translation override : this way, you don't have to edit files, and your changes will not be removed after an update!
A quick tutorial video to know this "hidden" secret of Joomla :
icagenda.joomlic.com/docs/documentation/...joomla-administrator
Then, use this tool to search all strings of translations where "event" is used, and create your custom strings with the name you want
Hope this helps ?
Best Regards,
Cyril