Personal pronouns take the place of specific nouns (the names of people, places or things). Basically, they are used instead of a specific name to avoid repetition and to help ease the flow of sentences.
We usually inject personal pronouns into a sentence when the name of the noun has been previously mentioned, so that the reader will know what is being referred to. For example:
In the second sentence, there are two personal pronouns. The personal pronoun "he" takes the place of "Richard" while the personal pronoun "it" takes the place of "laptop."
In this article you can review a list of personal pronouns, as well as examples of their various uses.
There are two types of personal pronouns: subject and object.
Subject Pronouns - I, You, He, She, It, They, We. Subject pronouns replace the name of the subject in the sentence.
Object Pronouns - Me, You, Him, Her, It, Us, Them. Object pronouns take the place of the object in the sentence (the noun that receives the action in a sentence).
Personal pronouns help us avoid constantly repeating the same noun over and over. The noun that is replaced is called the antecedent. Paying close attention to the antecedent will help you choose the correct personal pronoun.
To avoid confusion in sentences, it is important to choose the right personal pronoun that agrees in number (singular or plural), person (first, second, or third person), gender (masculine, feminine, neuter), and case (subject, object, possessive).
Another source of headache is the use of the subject pronoun "I" and the object pronoun "me."
If you need more information there are many other resources on YourDictionary on the subject of pronouns.