A method, performed by an electronic apparatus, of synthesizing speech from text, the method comprising: obtaining text input to the electronic apparatus; obtaining a text representation of the text by encoding the text using a text encoder of the electronic apparatus; obtaining a first audio representation of a first audio frame set of the text from an audio encoder of the electronic apparatus, based on the text representation; obtaining a first audio feature of the first audio frame set by decoding the first audio representation of the first audio frame set; characterized by: obtaining a second audio representation of a second audio frame set of the text based on the text representation and the first audio representation of the first audio frame set; obtaining a second audio feature of the second audio frame set by decoding the second audio representation of the second audio frame set; generating feedback information by combining audio feature information of at least one audio frame of the second audio frame set with compression information about the at least one audio frame of the second audio frame set; obtaining a third audio feature of a third audio frame set of the text succeeding the second audio frame set by encoding the generated feedback information; and synthesizing speech corresponding to the text based on at least one of the first audio feature of the first audio frame set, the second audio feature of the second audio frame set, or the third audio feature of the third audio frame set. obtaining text input to the electronic apparatus; obtaining a text representation of the text by encoding the text using a text encoder of the electronic apparatus; obtaining a first audio representation of a first audio frame set of the text from an audio encoder of the electronic apparatus, based on the text representation; obtaining a first audio feature of the first audio frame set by decoding the first audio representation of the first audio frame set; characterized by: obtaining a second audio representation of a second audio frame set of the text based on the text representation and the first audio representation of the first audio frame set; obtaining a second audio feature of the second audio frame set by decoding the second audio representation of the second audio frame set; generating feedback information by combining audio feature information of at least one audio frame of the second audio frame set with compression information about the at least one audio frame of the second audio frame set; obtaining a third audio feature of a third audio frame set of the text succeeding the second audio frame set by encoding the generated feedback information; and synthesizing speech corresponding to the text based on at least one of the first audio feature of the first audio frame set, the second audio feature of the second audio frame set, or the third audio feature of the third audio frame set. obtaining a second audio representation of a second audio frame set of the text based on the text representation and the first audio representation of the first audio frame set; obtaining a second audio feature of the second audio frame set by decoding the second audio representation of the second audio frame set; generating feedback information by combining audio feature information of at least one audio frame of the second audio frame set with compression information about the at least one audio frame of the second audio frame set; obtaining a third audio feature of a third audio frame set of the text succeeding the second audio frame set by encoding the generated feedback information; and synthesizing speech corresponding to the text based on at least one of the first audio feature of the first audio frame set, the second audio feature of the second audio frame set, or the third audio feature of the third audio frame set.