Spanish phrase
Estoy en contra.
Meaning
I am against it.
When to use it
States firm opposition, used to politely refuse a suggestion.
Example dialogue
¿Qué te parece cambiar la reunión al viernes?
What do you think about moving the meeting to Friday?
Estoy en contra de cambiarla, el viernes no puedo.
I am against changing it; I can't on Friday.