A close relative of mine would go to Christian refugee in Europe every year for two weeks over a period of nine years. He told me about a time when he thought a man spoke English and so he spoke to the man in English, but the man did not speak English. They understood each other well and each spoke in their own language. After an hour he realized the man did not speak English and was a Kurd who left his homeland. Another man who was there had a similar with a man who only spoke Swahili. Each man spoke in their own language and understood what the other was saying. The African man did not speak English and the other man did not speak Swahili. They spoke for two hours.