The intertwining of discourse, syntax, and lexicon in language use

The paper analyzes pleonastic conditionals (e.g., sweetheart, I understand. If you have to go, you have to go) in Huasteca Nahuatl, an Uto-Aztecan language spoken in Mexico. Based on conversational data, it is demonstrated that pleonastic conditionals in Huasteca Nahuatl have different discourse-pragmatic functions, such as surprise, disagreement, and indifference, etc. Moreover, it is argued that the different discourse-pragmatic functions of pleonastic conditionals are systematically associated with specific syntactic forms of the apodosis (i.e., whether the apodosis is a precise echo of the protasis or not) and with specific lexical preferences (i.e., verb lemmas appearing in the protasis and apodosis). It is proposed that these preferential co-occurrences are shaped by three usage-based factors: iconicity, discourse economy, and semantic coherence.