How many languages do linguists have to know?
All linguists are exposed to data from a number of languages, but may only be able to speak their own native language proficiently. In the real world, linguists speak about 2-4 languages proficiently (we did get into this because we liked foreign languages!) and are well-acquainted data from about 5-15 languages depending on experience and interests. But few honest linguists will claim to be proficient in 80 languages!