Just completed Hindi tree - how to do I get to level 25?
It is a great feeling - I have just made my Hindi tree golden at level 20, and I received a golden owl. How do I achieve level 25 without repeating the old lessons? Also congratulations to the Duolingo Hindi team, you have done a great job and I look forward to further updates.
I think you can't. You have to work again on what you've learned so that you can reach level 25 (it's never a bad thing to train!)
You could do timed practice and untimed practice to have more variety and to be less influenced by the name of the skill you practice. And I think that timed practice is a lot faster. For some languages I have the impression that you get some words and sentences only in timed and untimed practice. I don't know for Hindi though.