Review of how to form "dg": The "dg" sound is actually made up of two different sounds: “d” and “zh”. To form this sound, begin by rounding your lips in a circle. Then, place the tip of your tongue behind your upper front teeth at the back of the ridge, just before the roof of your mouth arches up. Press the sides of your tongue against your upper side teeth in the back of your mouth. Hold your breath and then force your voice through the small groove made by your tongue, producing a friction sound. This is a voiced sound, so you should hear your voice when you say it.