Answer:
People who were a part of the Spanish expeditions did not only brought friars, or soldiers. Some of these people were scholars who were responsible for so many things and acquired multiple knowledges in many fields. There was Pigafetta who was the Magellan's chronicler for example. I believe he was Italian, but we can also say that he does some of the expedition's laboral work. Some of these people are priests. And priests or friars back then were usually the highly educated ones in Europe.
So prior to first contact, both parties rely on body language. The same thing you do when you go for a vacation in a country where nobody speaks English; a charade-like type of communication. After some time, the more scholarly of the expedition (again this will be mostly friars) will try to learn the language of the natives and take note of the words that they used then categorize it systematically in an academic or scholarly manner. Once the priest has been able to speak the language enough for the natives to understand, regardless how wrong the grammar is, then we can say the breakthrough is done.
Explanation:
Sana makatulong po ako
