Review of how to form voiced "th": Open your mouth and stick your tongue out slightly. Let your upper front teeth rest very lightly on your tongue. Push your voice out through the tiny space between your upper front teeth and tongue. Keep your tongue and teeth in contact while you are pushing out the sound. This is a voiced sound, so you will hear your voice when you say it, and you should feel your tongue vibrate as you continue the sound.
Learn how to pronounce the voiced "th" sound
Click on the sound below that you would like to practice.