Quechua ("qheshwa") is an indigenous language of the Andean region, spoken today by approximately 13 million people in Bolivia, Peru, Ecuador, Northern Chile, Argentina, and Southern Colombia. It was the official language of Tawantinsuyu, the Inca Empire.
Quechua is a perfectly regular language, which makes learning the basics quite easy. However, a large number of suffixes and infixes can be added to words to change both overall significance and subtle shades of meaning, which leads to a rare expressiveness. Above the beginning level, Quechua requires some vast changes of mind-set as learners try to master bipersonal conjugation, conjugation dependent on mental state and veracity of knowledge, spatial and temporal relationships, and numerous cultural factors.