Korean is the most difficult language to learn for native English speakers, a U.S. state training agency on foreign affairs said.
In its latest report, released on Nov. 29, the Foreign Service Institute (FSI) designated Korean as a Category IV language that is "exceptionally difficult for native English speakers."
The category contains Arabic, Chinese and Japanese. The agency said at least 2,200 hours (88 weeks) of studying are needed to speak Korean.
"The languages included in category four are extremely difficult for native English speakers to learn," the FIS wrote on its website.
The report sorted 70 languages into four categories, depending on the level of difficulty.
Category III (hard languages) has 50 languages, including Russian, Vietnamese, Thai, Hungarian, Bulgarian, Greek and Polish. These languages require 1100 hours (44 weeks) of studying.
Category II has five languages -- German, Indonesian, Malaysian, Swahili and Haitian -- that require native English speaks to study for 900 hours to communicate with them.
Category I holds nine languages that are the easiest to learn for English speakers. They are Spanish, Italian, French, Romanian, Swedish, Portuguese, Norwegian, Danish and Dutch. The agency said 600 hours of learning would be enough to use them.