Number
The first subdivision of first-person pronouns is in number. 'I,' 'me,' 'my' and 'mine' are used when the speaker is only referring to him or herself and no one else is around, such as:
- I walked to school today by myself.
- Mom gave me $10 for lunch.
'We,' 'us,' 'ours' and 'our' are used when the speaker is part of a group of people, such as:
- We finished our group project in the library.
- Mom gave us each $10 for lunch.
Possession
The pronouns 'mine' and 'our' are a special class known as possessive pronouns. They are used by the speaker to show possession or ownership:
- That iPod is mine.
- My mom baked cookies.
- Our parents are out of town.
- The classroom is ours because the teacher left the room.
Subject and Object
So, you may be following along and understanding these divisions, but have you also noticed an odd pattern? There are two first-person singular pronouns and two first-person plural pronouns. Similarly, there are two different first-person singular possessive pronouns and two different first-person plural possessive pronouns.
This brings us to the last and trickiest division, between subject and object. 'I,' 'we,' 'my,' and 'our' are subjective pronouns, used when the speaker is doing the action in the sentence or the grammatical subject. 'Me,' 'us,' 'mine,' and 'ours,' conversely, are objective pronouns, used when the speaker is the grammatical object, having the action done to them.
So, the subjective pronouns are used in situations like this:
- I am going to Spain.
- We need to rush to make it to school.
- My teacher is Ms. Maple.
- Our school project is not going to be done in time.
In all of these examples, the speaker is doing the action. Compare with these examples:
- The teacher gave me an F.
- Miss Maple is going to fail all of us.
- That sweater you stole is mine.
- The red house on the left is ours.
In these, the speaker is the grammatical object, having the action done to it.