The spelling of the phrase "marches up cannon mouth" may seem peculiar, but it can be explained through phonetics. The first word, "marches", is pronounced /ˈmɑrtʃɪz/, with the "ch" sound representing the voiceless postalveolar affricate. The word "up" is pronounced /ʌp/, with the "u" sound representing the schwa vowel. "Cannon" is pronounced /ˈkænən/, with the "a" sound representing the short vowel, and the "n" sound being nasalized. Finally, "mouth" is pronounced /maʊθ/, with the "ou" representing the diphthong vowel sound.