English Translation
Before you organize the event, speak up.
It should be:
Antes de que organices el evento, habla.
or
Antes de que organice el evento, hable.
The way it currently is written is a mix of Ustedes and Tu.
Before you organize the event, speak up.
It should be:
Antes de que organices el evento, habla.
or
Antes de que organice el evento, hable.
The way it currently is written is a mix of Ustedes and Tu.