This study introduces set-denoting time expressions in Korean, which can be divided into simple and complex types. It was found that while the simple type expressions are easily represented within ISO-TimeML, a time-expression markup language, some complex type set-denoting expressions are not. Therefore, this study analyzes the reason for these difficulties in representing complex type expressions, as well as suggests the introduction of @measure and @interpretation attributes in the TIMEX3 tag. The @measure attribute represents the time interval, and the @interpretation attribute is used to distinguish distributive readings from cumulative readings. Additionally this paper suggests that a mapping between these and other attributes are required in TLINK.