1. A method of recognizing a keyword in a speech, comprising: on an electronic device: receiving a sequence of audio frames comprising a current frame and a subsequent frame that follows the current frame; determining a candidate keyword for the current frame using a predetermined decoding network that comprises keywords and filler words of multiple languages, associating the audio frame sequence with a confidence score that is partially determined according to the candidate keyword; identifying a word option for the subsequent frame using the candidate keyword and the predetermined decoding network; when the candidate keyword and the word option are associated with two distinct types of languages, updating the confidence score of the audio frame sequence based on a penalty factor that is predetermined according to the two distinct types of languages, the word option and an acoustic model of the subsequent frame; and determining that the audio frame sequence includes both the candidate keyword and the word option by evaluating the updated confidence score according to a keyword determination criterion.
1. A method of recognizing a keyword in a speech, comprising: on an electronic device: receiving a sequence of audio frames comprising a current frame and a subsequent frame that follows the current frame; determining a candidate keyword for the current frame using a predetermined decoding network that comprises keywords and filler words of multiple languages, associating the audio frame sequence with a confidence score that is partially determined according to the candidate keyword; identifying a word option for the subsequent frame using the candidate keyword and the predetermined decoding network; when the candidate keyword and the word option are associated with two distinct types of languages, updating the confidence score of the audio frame sequence based on a penalty factor that is predetermined according to the two distinct types of languages, the word option and an acoustic model of the subsequent frame; and determining that the audio frame sequence includes both the candidate keyword and the word option by evaluating the updated confidence score according to a keyword determination criterion. 2. The method of claim 1 , wherein a plurality of candidate keywords, including the candidate keyword, are determined for the current frame of the audio frame sequence, and each candidate keyword is associated with at least one word option, and wherein a subset of the plurality of candidate keyword are determined to be included in the audio frame sequence together with their respective at least one word options based on the keyword determination criterion.