Nothing can distinguishes se and ce when you hear them. However, they have completely different meanings:
- you will always find se (or s' ) in front of a verb
e.g.: se souvenir -> to remember.
It refers to a person as me or te do, they are called "pronoms personnels réfléchis".
Let's now conjugate se souvenir:
Je me souviens
Tu te souviens
Il se souviens
Nous nous souvenons
Vous vous souvenez
Ils se souviennent
- ce will always be found in front of a noun. The feminine of ce is cette.
e.g.: ce cahier -> this notebook
cette chaise -> this chair
Ce is used in the same place than le. However, there is a difference of degree between these two determinants: ce is more vague than le. The same difference applies to the (= le) and this (= ce).