633 The interrogatives -sa and -ti elicit answers with -wa or -pi even if no information is available. Jani.w yat.k.t.ti. 'T don't know.' (general) no ~ know 1-3 S On the other hand, the final suffix -xa or its variant is nonabsolute, often tentative. The limited final suffix -chi- and the disclaimer -m are the strongest indirect knowledge markers, the former very similar in both phonologi- cal shape and semantics to the Non-involver suffix -chi. In fact, the final suffix combinations -chi.xa and -chi.m have occurred only with -chi Non-involver on the verb, although the latter often occurred without -chi.xa or -chi.m in the sentence. Combining direct knowledge tenses with direct knowl- edge final suffixes reinforces the directness. The final suffixes -wa and -pi do not co-occur with the Non-involver, the most indirect of the tense markers. At this stage of research no regional variation in this postulate has been noted, but there is variation with respect to Missionary Aymara (see 9-6.13).