As others have commented already: Most people in Europe can speak at least two languages, and even the minority who can just speak one can typically understand several. Even my old parents, when they were alive, could understand at least three languages, and English wasn't one of them. Africa? Most people can handle several languages. South Africa, for example, has 11 official languages, people can often speak a bunch of them and understand several more. Asia? Varies, but multi-lingual is common in many regions, though not so much in Japan.

It's not that you have to be able to speak multiple languages, understanding several is still common.