را

In a sentence

• کتاب را می‌خوانم.

  I read the book.

  The word "را" is used to mark "کتاب" (the book) as a definite direct object in this sentence.

• دوستم را دیدم.

  I saw my friend.

  The word "را" is used to indicate that "دوستم" (my friend) is the particular direct object that was seen here.

• این غذا را دوست دارم.

  I like this food.

  Here, "را" marks "این غذا" (this food) as the direct object related to the subject's action of liking.