This world is full of thousands of languages. Wikibooks also hosts many different language learning books, but on a smaller scale, of course.
Becoming fluent in a language is no walk in the park, even if you do already display an aptitude for languages. This Wikibook will act as a very useful guide showing how difficult learning any particular language you have set your eyes on is.
Many people wonder how long it will take them to become proficient in a certain language. This question, of course, is impossible to answer because a lot depends on a person's language learning ability, motivation, learning environment, intensity of instruction, and prior experience in learning foreign languages. Last, but not least, it depends on the level of proficiency the person wishes to attain.
The Foreign Service Institute (FSI) of the US Department of State has compiled approximate learning expectations for a number of languages based on the length of time it takes to achieve Speaking 3: General Professional Proficiency in Speaking (S3) and Reading 3: General Professional Proficiency in Reading (R3). The list is limited to languages taught at the Foreign Service Institute, minus languages which don't have their own Wikibook. Note that this only states the views of The Foreign Service Institute (FSI) of the US Department of State, and many language learners and experts would disagree with the ranking. It must also be kept in mind that students at FSI are almost 40 years old, are native speakers of English and have a good aptitude for formal language study, plus knowledge of several other foreign languages. They study in small classes of no more than six. Their schedule calls for 25 hours of class per week with three or four hours per day of directed self-study.
Before you even look at the table, here's a little advice: If you find that the language you want to learn is particularly difficult, don't let that stop you from learning it. They may well be difficult, but that doesn't mean they're impossible to learn (and once you do learn it, it will be much more rewarding)! Also remember that the Foreign Service Institute may have gotten things wrong.
Now for the part you've all been waiting for. "How difficult will learning language x be?". Well, now you can find out what the FSI thinks.
|Category I: "Easy languages" – Languages closely related to English|
24–30 weeks (600–750 class hours)
|French (30 weeks)|
|Category II: Languages with some linguistic and/or cultural differences from English – "Intermediate languages"|
Approximately 36 weeks (900 class hours)
|Category III: Languages with significant linguistic and/or cultural differences from English – "Hard languages"|
Approximately 44 weeks (1100 class hours)
|Persian (Dari, Farsi, Tajik)|
|Category IV: "Super Hard languages" – Languages which are quite difficult for native English speakers|
88 weeks (2200 class hours, about half that time preferably spent studying in-country)
|Taiwanese (Hokkien Min Nan)|
*Languages preceded by asterisks are typically somewhat more difficult for native English speakers to learn than other languages in the same category.
Many people in the conlang community attempt to design international auxiliary languages specifically designed to be much easier to learn than natural languages.