In short, there is still much work to do regarding the interaction betweeen Spanis and Indian launguages. In modern America and Central Europe the dominant language is Spanish, speakers of all Mesoamerican Indian languages include some who are bilingual: few languages are spoken by people completely bilingual, most indigenous languages are spoken by populations that can be that are at least 50% of monolingual speakers. All Mesoamerican languages with a significant number of bilingual speakers have been influenced by Spanish, primarily in areas of vocabulary, particles and word order. Since the conquest of Spain Mesoamerican languages have been borrowing words from Spanish, and since the type of Spanish spoken has changed somewhat over the years both in vocabulary and pronunciation, we can distinguish different historical periods in loan words. For a variety of reasons, certain function words like conjunctions or adverbs are often borrowed from Spanish: but since, until, and, or, nor, even, if, when, why, why, then. Some languages have assimilated the word order of subject-verb-object. Unlike the Spanish of Mesoamerica has been the recipient of vast amounts of lexical material in local languages, primarily the Nahuati, The loan has come from names of plants, animals, artifacts, and indigenous forms that were missing in Mesoamerica and Spanish. Among the reasons Nahuati has been the predominant source is that the Aztecs were the first Mesoamerican people conquered by the Spanish, the Aztecs had been in many parts of Mesoamerica, the Spanish recruited Aztecs, particularly as guides in their military forces to assist his quest to subdue the rest of Mesoamerica, and for several decades, Azteca, written spelling Roman was used in many parts of Mesoamerica to the official records of documents, wills and censuses.