隔音符號

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First used in the draft of the Scheme for the Chinese Phonetic Alphabet (漢語拼音方案) published in February 1956 by the Committee for the Reform of the Chinese Written Language (中國文字改革委員會).

隔音符號

1. apostrophe used to divide syllables within a word to avoid ambiguity in various alphabetic systems used in China; in pinyin, to be used between two syllables in a word (unless a hyphen is being used) whenever the second syllable begins with an a, o or e (regardless of whether any ambiguity exists) and not in any other circumstance

   • a，o，e開頭的音節連接在其它音節後面的時候，如果音節的界限發生混淆，用隔音符號（’）隔開，例如：pi’ao（皮襖）。
     a，o，e开头的音节连接在其它音节后面的时候，如果音节的界限发生混淆，用隔音符号（’）隔开，例如：pi’ao（皮袄）。

     From: 1958, 汉语拼音方案 (Scheme for the Chinese Phonetic Alphabet), section 5

     a, o, e kāitóu de yīnjié liánjiē zài qítā yīnjié hòumiàn de shíhou, rúguǒ yīnjié de jièxiàn fāshēng hùnxiáo, yòng géyīn fúhào (’) gékāi, lìrú: pi’ ao (pí'ǎo).

     , when a syllable beginning in a, o or e is preceded by another syllable, if the division between the syllables is unclear, use the syllable-dividing apostrophe (’) to divide . For example: pi’ao 皮襖／皮袄 (pí'ǎo).

   • 壯文的多音詞主要是根據聲韻結構和聲調符號來識別音節……當據此仍不好區分音節時，就得利用隔音符號“’”來劃分
     壮文的多音词主要是根据声韵结构和声调符号来识别音节……当据此仍不好区分音节时，就得利用隔音符号“’”来划分

     From: 1981, 壮文方案（修订案）

     Zhuàngwén de duōyīncí zhǔyào shì gēnjù shēngyùn jiégòu hé shēngdiào fúhào lái shíbié yīnjié...... Dāng jù cǐ réng bùhǎo qūfēn yīnjié shí, jiù děi lìyòng géyīn fúhào “’” lái huàfēn

     In Zhuang, syllables in multisyllabic words are distinguished according to the syllable structure and tone symbols... When the syllables still cannot be distinguished accordingly, an apostrophe "'" needs to be used to divide the syllables

• (obsolete) 界音符號／界音符号 (jièyīn fúhào)

• 撇號／撇号 (piěhào)
• 聲調符號／声调符号 (shēngdiào fúhào)

• Apostrophes in Hanyu Pinyin: when and where to use them, Pīnyīn.info