The adopting proclamation stated that the Pyongan dialect spoken in the North Korean capital Pyongyang and its surroundings should be the basis for Munhwaŏ.

Thus, while the first group indicate that, besides the large divergence at the level of vocabulary, differences between the North and South Korean standards also include phonetic and phonological features, as well as stress and intonation,[2] the others consider these differences attributable to replacement of Sino-Korean vocabulary and other loanwords with pure Korean words, or the Northern ideological preference for "the speech of the working class" which includes some words considered non-standard in the South.

In the second period, efforts were made to simplify and standardize academic, technical, and Sino-Korean terms, leading to some degree of language differentiation between the North and South.

[6] North Korea's vocabulary maintenance, managed mainly by the National Language Decision Committee, was recorded in a work titled "Tatumunmal", accumulating up to 50,000 words by 1976.

The Korean dictionary serves to establish and control the usage of Mwunhwae vocabulary, requiring all users, including individuals and national institutions, to adhere strictly to its prescriptions.

The idiolect and style of Kim Il Sung, North Korea's first leader, significantly influence this language standard, as his words often become Munhwaŏ without restraint.