Here's why:
* Personal pronouns refer to specific people or things. They change based on the person, number, and gender of the noun they replace.
* Subject pronouns are the specific personal pronouns used when the pronoun is the subject of the sentence (the one performing the action).
Here's a table showing some subject pronouns and their corresponding personal pronoun categories:
| Subject Pronoun | Person | Number | Gender |
|---|---|---|---|
| I | First | Singular | - |
| You | Second | Singular/Plural | - |
| He | Third | Singular | Masculine |
| She | Third | Singular | Feminine |
| It | Third | Singular | Neuter |
| We | First | Plural | - |
| They | Third | Plural | - |
Examples:
* I went to the store. (Subject pronoun "I" is the one performing the action of going)
* They are playing in the park. (Subject pronoun "they" are performing the action of playing)
So, a subject pronoun is always a personal pronoun, but not all personal pronouns are subject pronouns. There are also object pronouns (me, you, him, her, it, us, them) which function as the object of a verb or preposition.