Sudo, Y. (2010). The syntax and semantics of indexical shifting in modern uyghur. Unplished Generals Paper. Link
All natural languages known so far have expressions referring to certain aspects of the context of utterance. In English, for example, the expression me refers to the speaker in the context of utterance,1 and does not have a fixed referent unlike proper names. More concretely, when you and I say me, this single word refers to two different individuals, whereas when we say Plato, we talk about the same man.
Such expressions whose semantic values are contextually determined are widely called indexicals and we adopt this terminology in this paper. Besides 1st person pronouns, 2nd person pronouns, temporal adverbials such as now and yesterday, and locative adverbials such as here and there are also indexicals.2
Although every natural language seems to have indexicals, there is a cross-linguisitic variation regarding their interpretation. Namely, in certain constructions in certain languages, the interpretation of indexicals can be relative to contexts other than the one in which the utterance is being made, a phenomenon we refer to as indexical shifting. In this paper we provide novel empirical data of indexical shifting from Modern Uyghur (henceforth Uyghur) and discuss its theoretical consequences. For the rest of this introductory section, we review the issues indexical shifting poses to the semantic theory of indexicals.
Pretty cool paper on Uyghur linguistics from MIT.