4. Mouth
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Extrude again. Hit
G
to repeat extrude.
11.
12.
It will be the inside of the mouth. Scale up the selected faces.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.