The American languages have a structure so different from Latin that the Jesuits, who look carefully to anything that might favor a quick establishing of missions, introduced the richer Indian languages, especially Quechua and Guarani, instead of Spanish, to their converts because these languages were systematic and already widespread. They tried to substitute these poorer, coarser dialects with irregular constructions. They found this substitution easy; Indians from different tribes docilely learned them, and these languages became a medium of communication between missionary and Indian. Through these languages the Jesuits found it easier to link the various tribes until then separated from each other by language.