• Personal pronouns are amongst the oldest known words including, he, she, it, I, we, you and they.

• Five out of all personal pronouns have two forms, objective form (me, us, him, her and them) and a subjective form (I, we, he, she and they).
• The mistakes that commonly occur are due to the reversal of objective and subjective forms.
• Further, two more errors that are increasing include:
• The personal pronoun is being replaced by a pronoun ending in –self.
• The personal pronoun is used in a context that referrers to a possessive adjective.

• Mistake #1: Subject form replaced by Object form
• Incorrect: My colleagues and me will be debating a suitable way to do it during the next several weeks. (Jay Inslee, Congressional Record)
• Correct: My colleagues and I will be debating a suitable way to do it during the next several weeks.
• The subject of a verb consists of the subject forms (I, we, he, she and they) of personal pronouns. Here is the model for appropriate usage:

“We have gone through a lot of difficulties. (Subject of the verb gone)

The kids and I were enjoying playing. (Subject of the verb enjoyed)

My friends and I will be going to California as soon as possible. (Subject of the verb will be going) ”

• Mistake #2: Object form replaced by subject form after a preposition 
• Incorrect: She tried to make everyone happy by taking pictures and spending quality time one by one with they and the kitten. (The person having an M.A. degree gave the statement)
• Correct: She tried to make everyone happy by taking pictures and spending quality time one by one with them and the kitten.

The object form is used when the pronoun is the object of a preposition.

Reminder: These are included in preposition with, under, in, on, to and between. Here are two illustrations related to accurate usage:

“The dog starts barking at him after seeing a piece of chicken in his hand. (Object of the preposition at)

She gave gifts to John and me. (Object of the preposition to) “

• Mistake #3: Object form replaced by Subject form next to a transitive verb
• Incorrect: Robbers start following she and her daughter out of a shopping mall. (Source: New York Daily News)
• Correct: Robbers start following her and her daughter out of a shopping mall.

The object form is necessary when a pronoun is the direct object of a transitive verb. An example of correct usage is giving below:

 “The coach praised them for their good performance in the match. (Direct object of the verb praised)”

Mistake #4: The corresponding possessive adjective replace by Subject form

• Incorrect: Jenna accepted she and her friend’s involvement in a bank robbery. (Source: Downtown Abbey site)
• Correct: Jenna accepted her and her friend’s involvement in a bank robbery in front of the police. 

Note: The corresponding possessive forms are associated with personal pronouns.

Your, her, his, our, their and it’s are the possessive adjective forms. These forms stand in front of the possessed nouns. Examples:

 “Rahim is their friend. (Personal pronoun they is associated with a possessive adjective)

Bonney is her cousin. (Personal pronoun she and her is associated with a possessive adjective)”

Mistake #5: The personal pronoun is replaced by Reflexive Pronoun

• Incorrect: All of my friends and my enjoyed watching the movie and hanging out with each other.
• Correct: All of my friends and I enjoyed watching the movie and hanging out with each other.

 “Reflexive pronouns” or “Emphatic pronouns” are the ones that end up with – self or –selves. Some examples related to their correct usage are below:

“The owner of the pizzeria himself delivered my pizza today. (Emphatic pronoun) 

The girl tried to cut herself with a scissor. (Reflexive pronoun)”

• There could be some events where emphatic pronouns are used for verbal display but in normal speech, it is not a standard to replace a personal pronoun ending with -self or –selves but to avoid it.