1946年,奥德里库尔构拟了初步的原始克伦语,并于1953年和1975年进行了部分修订。
奥德里库尔将比较法应用于波克伦语和斯高克伦语两种克伦语,数据来自W. C. B. Purser和Saya Tun Aung的《波克伦语方言比较词典》(1922)。
每种语言都有6个声调,4个在开音节中,2个是入声并以声门塞音结尾。
通过比较这些声调间对应的词汇,奥德里库尔建立了8个对应集,后来戈登·卢斯(Gordon Luce)将其分别称为I到VIII调,其中有6个在开音节,2个是入声。
两种语言的声母很相似,塞音区分送气、不送气和内爆音对立,且只有浊响音。
内爆音和响音可以直接对应,送气和不送气则可以分出3种对应的情况。
这些特殊对应只出现在2个特定的声调:[1]:33, 35[2]:5–7, 12–13[3]:328–329
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———. Le système des tons du karen commun. Bulletin de la Société de Linguistique de Paris. 1975, 70 (1).:339–343
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