how do you type the tones in duolingo ?
http://www.pinyintones.com/ might be of use. Typing pinyin is not required in the Duolingo course, however.
Wow! You have a lot of languages!
wouldn't it be so much easier for duolingo to accept an answer like ni3 hao3? then nobody has to install pinyin on their computer nor do some copy pasting from some other website...