Duolingo adds Mandarin course to its language library

Online language learning company Duolingo has finally added a Mandarin course to its offerings. With more than one billion speakers, Mandarin is the most popular language on the planet, but it's also on one of the hardest to learn, which is why the course will prove a little beefier than its European language counterparts. English speakers will learn the language's characters as well as the four tones of Mandarin, with lessons structured by themes such as greetings, food, health and sports.

The course will be particularly helpful for people doing business in China, with a business and finance section putting emphasis on phrases such as "Have you read the contract?" and "We would like to invest in your company". Although for all of Duolingo's successes, it probably isn't advisable to conduct million-dollar deals with only a language app to help with the fine print. It's available now on iOS and Android.