Most common:
* vraiment: This is the most common and versatile translation, used in most situations. It carries a similar meaning to "really" in English.
* en effet: This translates to "in effect" and is used to emphasize a point or to give a reason for something. It's often used in formal writing and speech.
Other options:
* véritablement: This is a more formal and literary translation, often used in writing.
* sincèrement: This means "sincerely" and is usually used in formal contexts, like letters or speeches.
* effectivement: This translates to "effectively" and is used to emphasize a point or to confirm something.
Examples:
* "C'est vraiment beau." (It's really beautiful.)
* "Il a fait froid aujourd'hui, en effet." (It was really cold today, indeed.)
* "C'est un véritable plaisir de vous rencontrer." (It is a real pleasure to meet you.)
* "Je vous remercie sincèrement pour votre aide." (I sincerely thank you for your help.)
* "Il a effectivement raison." (He is effectively right.)
The best translation will depend on the specific context and the nuance you want to express.