Method and Conclusion. See here.
Results. A ratings system was designed in terms of how difficult it would be for an English-language speaker to learn the language. In the case of English, English was judged according to how hard it would be for a non-English speaker to learn the language. Speaking, reading and writing were all considered.
Ratings: Languages are rated 1-6, easiest to hardest. 1 = easiest, 2 = moderately easy to average, 3 = average to moderately difficult, 4 = very difficult, 5 = extremely difficult, 6 = most difficult of all. Ratings are impressionistic.
Time needed. Time needed for an English language speaker to learn the language “reasonably well”: Level 1 languages = 3 months-1 year. Level 2 languages = 6 months-1 year. Level 3 languages = 1-2 years. Level 4 languages = 2 years. Level 5 languages = 3-4 years, but some may take longer. Level 6 languages = more than 4 years.
This post will look at the Kam languages in terms of how difficult it would be for an English speaker to learn it.
The Kam languages people are three closely related languages – Northern Dong, Southern Dong and Cao Miao. They are spoken by 1.5 million Dong people in southwest China and by a tiny population in a single village in Northern Vietnam. These languages were rated by the Fudan University study referenced above under Wu as the 2nd most phonologically complex on Earth (Wang 2012). There are 32 stem initial consonants, including oddities like tɕ, tɕʰ, pʲ, pʲʰ, ɕ, kʷ, kʷʰ, ŋʷ, tʃʰ, tsʰ. Note the many contrasts between aspirated and unaspirated voiceless consonants, including bilabial palatalized stops, labialized velar stops, and alveolar affricates. There are an incredible 64 different syllable finals, and 14 others that occur only in Chinese loans.
There are an astounding 15 different tones, nine in open syllables and six in checked syllables (entering tones). Main tones are high, high rising, high falling, low, low rising, low falling, mid, dipping and peaking. When they speak, it sounds as if they are singing.
The Kam languages get a 6 rating, hardest of all to learn.
Wang, Chuan-Chao et al. 2012. Comment on ”Phonemic Diversity Supports a Serial Founder Effect Model of Language Expansion from Africa.” Science 335:657.