Final answer:
Epenthesis is adding extra sound between two consonants for easier pronunciation, while metathesis is rearranging the order of sounds or syllables in a word.
Step-by-step explanation:
Epenthesis is a phonological process in which an extra sound (usually a vowel) is added between two consonants in order to make pronunciation easier. For example, in the word 'hamster,' the 'p' sound is added between 'm' and 's' resulting in 'hampster.'
Metathesis is a phonological process in which the order of sounds or syllables in a word is rearranged. An example of metathesis is the word 'aks' instead of 'ask.' This process often occurs to make pronunciation more efficient.