How to conjugate "Dürfen" with "Du" in German?

For example, the sentence "Du darfst das Fenster öffnen."

The correct form for "dürfen" in the second person singular is "darfst". In German, the verb "dürfen" (to be allowed to, can) is conjugated differently depending on the subject. For the second person singular, such as when addressing someone directly with "you" in English, "dürfen" is conjugated as "darfst." This form applies in sentences like "Du darfst das machen" (You are allowed to do that). This conjugation is part of the pattern in German where most verbs change their endings based on the subject's person and number, ensuring that the verb agrees with its subject. Remembering these conjugation patterns is crucial for correctly constructing sentences in German.