  It is commonly acknowledged that temporal expression extractors are important
components of larger natural language processing systems like information
retrieval and question answering systems. Extraction and normalization of
temporal expressions in Turkish has not been given attention so far except the
extraction of some date and time expressions within the course of named entity
recognition. As TimeML is the current standard of temporal expression and event
annotation in natural language texts, in this paper, we present an analysis of
temporal expressions in Turkish based on the related TimeML classification
(i.e., date, time, duration, and set expressions). We have created a lexicon
for Turkish temporal expressions and devised considerably wide-coverage
patterns using the lexical classes as the building blocks. We believe that the
proposed patterns, together with convenient normalization rules, can be readily
used by prospective temporal expression extraction tools for Turkish.
