mɔ̃
* m as in "me"
* ɔ̃ as in "on" (the "on" in "on the road")
It's important to note:
* The "n" is silent.
* The "o" has a nasal sound, similar to the "on" sound in English.
Therefore, the pronunciation is close to "mon" in English, but with a slightly different vowel sound.