Formal:
* Comprendre l'anglais: This is the most literal and formal translation.
* Maîtriser l'anglais: This means to master English, implying a high level of understanding.
Informal:
* Parler anglais: This literally means "speak English" but can also be used to mean "understand English."
* Savoir l'anglais: This means "to know English," implying some level of understanding.
More specific:
* Comprendre l'anglais parlé: This means to understand spoken English.
* Comprendre l'anglais écrit: This means to understand written English.
Example sentences:
* Je comprends l'anglais. (I understand English.)
* Je parle anglais. (I speak English. This implies you also understand English.)
* Je maîtrise l'anglais. (I master English.)
* Je comprends l'anglais parlé, mais pas l'anglais écrit. (I understand spoken English, but not written English.)
The best way to say "understand English" in French depends on the specific context and the level of formality you want to convey.