Formal:
* Ele se lembra: This is the most common and direct way to say "he remembers."
* Ele recorda: This is a more formal way of saying "he remembers" and is often used in written language.
Informal:
* Ele lembra: This is a more casual and colloquial way of saying "he remembers."
Other options:
* Ele tem lembranças: This means "He has memories."
* Ele não esquece: This means "He doesn't forget."
The best option will depend on the specific context and the level of formality you want to convey.