Mandarin Chinese

Sorbian languages

There are approximately 7,000 languages globally; one language goes extinct roughly every two weeks

OK gesture

OK's universal recognition traces back to the 1830s, origins debated

Basque language

Basque is a language isolate — unrelated to any other known language on Earth

English alphabet

Hawaiian alphabet: 13 letters (5 vowels, 8 consonants)

Mongolia

Mongolia: 2 people/sq km

Longest word in English

The longest word in English without a repeated letter is 'uncopyrightable' — 15 letters