问题：
broad transcription adn narrow transcription (宽式标音
答案：
Two ways to transcripe speech sounds are availabel. One is the transcription with letter-symbos only and the other is the transcription with letter-symbols together with the diacritics (变音符). The former is called broad transcription. This is the transcription normally used in dictionaries and teaching textbooks for general purposes. The latter, i.e. the transcription with diacritics, is called narrow transcription. This is the transcription needed and used by the phoneticians in their study of speech sounds. With the help of the diacritics they can faithfully represent as much of the fine details as it is necessary for their purpose.