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 Malay and Bahasa Indonesia languages in terms of how difficult it would be for an English speaker to learn it.
Bahasa Indonesia is an easy language to learn. For one thing, the grammar is dead simple. There are only a handful of prefixes, only two of which might be seen as inflectional. There are also several suffixes. Verbs are not marked for tense at all. And the sound system of these languages, in common with Austronesian in general, is one of the simplest on Earth, with only two dozen phonemes. Bahasa Indonesia has few homonyms, homophones, homographs, or heteronyms. Words in general have only one meaning.
Though the orthography is not completely phonetic, it only has a small number of nonphonetic exceptions. The orthography is one of the easiest on Earth to use.
The system for converting words into either nouns or verbs is regular. To make a plural, you simply repeat a word, so instead of saying “pencils,” you say “pencil pencil.”
Bahasa Indonesia gets a 1.5 rating, extremely easy to learn.
Malay is only easy if you learn the standard spoken form or one of the creoles. Learning the literary language is quite a bit more difficult. However, the Jawi script, which is Malay written in Arabic script, is often considered to be perfectly awful.
Malay get a 2 rating for moderately easy.