Mouth.
This is my mouth.
I say something.
I stay quiet.
I open my mouth.
I close my mouth.
Lips.
These are my lips.
One lip.
Two lips.
I speak - my lips move.
I smile.
I laugh.
Tongue.
This is my tongue.
The tongue is in the mouth.
I show my tongue.
Teeth.
I have teeth in my mouth.