Formal:
* Je suppose (pronounced: juh soo-pohz) - This is the most direct and formal translation of "I guess."
* J'imagine (pronounced: zhee-mah-zheen) - This means "I imagine" and can be used similarly to "I guess" in certain situations.
Informal:
* Je pense (pronounced: juh pahns) - This means "I think" and is a more casual way to say "I guess."
* Je crois (pronounced: juh krwah) - This means "I believe" and can be used to express a tentative opinion.
* On dirait (pronounced: ohn dih-ray) - This means "It looks like" and can be used to express a guess based on appearances.
* Peut-être (pronounced: puh-tetr) - This means "maybe" and is a more uncertain way to express a guess.
Example:
"I guess I'll go to the party." can be translated as:
* Je suppose que j'irai à la fête. (formal)
* Je pense que j'irai à la fête. (informal)
* Peut-être que j'irai à la fête. (uncertain)
The best way to choose the right phrase depends on the situation and the level of formality you want to convey.