For example,
Country: Denmark
Languages: Danish
Ad copy: Danish
When I set the "Precise Interests", I use the Danish, there is so little audience, but if I use english, there is many audience.
Sorry for I asked such a childish question, but i am very confused. Thank you everyone.
It'll entirely depend on whether people tend to use Danish or English in their profiles - as I understand it, "Precise Interests" is initially driven by what people type into their profile.
Sounds like in Denmark most people fill in their FB details in English.
can't you just use both?
Yes, then which ad copy i should use? Danish or english?
for your example i would just use danish in the ad copy and use both the english and danish version in precise interests.