A method includes: converting a first utterance of a user into first text; segmenting the first text into a plurality of text segments, the plurality of text segments including a first text segment and a second text segment; classifying the first text segment as a first type that is mapped to intent information used to perform a task; classifying the second text segment as a second type that is not mapped to intent information used to perform a task; performing a first task based on first intent information corresponding to the first text segment, the first task including a device control operation on a target device; generating pairing information by pairing the first intent information with the second text segment; converting a second utterance of the user into second text; and based on identifying the second text segment in the second text, performing the first task using the pairing information.