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 Dzongka language in terms of how difficult it would be for an English speaker to learn it.
Sino-Tibetan
Tibeto-Burman
Western Tibeto-Burman
Bodish
Central Bodish
Southern
Dzongka, the official language of Bhutan, has some pretty wild phonology, in addition to having the crazy Tibetan writing system, this time using Bhutanese forms of the Tibetan script.
It contrasts all of the following: s, sʰ, ʰs, ʰsʰ, ts, ʰts, tsʰ, z, ʱz, dz, ʱdz, ⁿsʰ, ᵐtsʰ, ⁿtsʰ, ⁿdz, ᵖts, ᵖtsʰ, ᵖtsʷʰ, and ᶲs, and in addition, it has four tones, but there is no single word that is distinguished by tone only. On top of that, there are 22 different vowels. Dzongka phonology is clearly more than a mouthful.
Dzongka gets a 5 rating, extremely hard to learn.