Hello,
I wish to add my native language of Hindi as well on LingQ, if possible. How can I do it?
You can vote for that language at LingQ’s facebook page. We are adding one language per month. I am sure there are many people looking forward to having Hindi at LingQ. Here is the link.
Hindi is well down the list. It appears that Esperanto is on top right now. So get your friends to vote too.
steve, un idioma cada mes?
uAU, eso es un record, te felicito a tú y tu equipo
Done! Hindi is on top now! When will it be added now? 
A new language is set to be added on the first of each month. That means that if Hindi stays at the top we could see it as early as November 1st
I noticed that Hindi words get amputated when I try to LingQ them. I don’t know anything about Hindi morphology, but it happens even with the easiest sentences I could find. Someone who knows the Devanagari script might want to investigate further.
There is also the issue that Urdu is virtually the same language as Hindi written in a different script.
I had the same issue, testbed 1900. But since the script isn’t supported there is no surprise that the words won’t lingQ properly. As far as I can tell, each character is currently treated as a word (like I hear they do with Chinese). If Hindi becomes the next language then I’m sure they’ll fix that. For now you can do what I started to do, which is to use a variation of the Latin alphabet to approximate all the sounds. You can play around with different fonts to represent one of the two versions for the letters t, d, k, kh, sh, and r that the Hindi sound system distinguishes between (not to mention the four different ‘n’ characters). You may just want to wait since this is tedious and will be obsolete if the language makes it to beta. If it does I’m sure that they’ll allow both scripts since Urdu uses a modified version of the Arabic script, which is already in beta.