Immerse yourself as best as possible. If you’re learning Japanese, watch anime and J-dramas. If you’re learning Spanish, shop at local Mexi-marts and watch Telemundo. This was the game changer for me.

I've actually built something that you might find interesting. manalect.com

It's not exactly what JIVX is, but it can help you practice with sentences. And I'm currently working on a voice only mode.

It's something I'm still developing so it might have issues.