What are the rules for using reflexive pronouns in grammar syntax?

Reflexive pronouns are used when the subject and object of a sentence refer to the same person or thing. The rules for using reflexive pronouns in grammar syntax are as follows:

1. Reflexive pronouns are formed by adding "-self" (singular) or "-selves" (plural) to the end of the pronoun. For example: myself, yourself, himself, herself, itself, ourselves, yourselves, themselves.

2. Reflexive pronouns are used to emphasize the subject of the sentence and are not necessary for the sentence's meaning. They can be removed without changing the sentence's core meaning. For example: "I myself will do it" (emphasizing that I will do it) or "I will do it" (without emphasis).

3. Reflexive pronouns are used when the subject and object of a sentence are the same. For example: "He cut himself with a knife" (subject and object both refer to "he").

4. Reflexive pronouns are used after certain verbs that require them, such as "enjoy," "hurt," "introduce," "prepare," "teach," etc. For example: "She hurt herself while playing" or "They introduced themselves to the new neighbors."

5. Reflexive pronouns can also be used for emphasis or to show that an action is done independently. For example: "I made the cake myself" (emphasizing that I made it without help) or "The cat can clean itself" (showing that the cat can clean independently).

6. Reflexive pronouns are not used after prepositions unless they refer back to the subject. For example: "She bought a gift for herself" (referring back to "she") but not "She bought a gift for him herself."

It is important to follow these rules to ensure correct usage of reflexive pronouns in grammar syntax.