Final answer:
ASL mouth movements have two functions: rapid alternating movements for speech and lateral movement of the cheeks for oral functions.
Step-by-step explanation:
The two functions of ASL mouth movements are:
- Rapid alternating movements: These movements are important for speech and involve the tongue, lips, and palate. For example, a person might repeat nonsense consonants like "lah-kah-pah" to practice these movements.
- Lateral movement of the cheeks: This movement, such as sucking on a straw or compressing air in the mouth while blowing, helps with speech and other oral functions.