Most Common Grammar Mistakes in English - I or Me?

Subject pronouns and object pronouns

Wrong: He sat between you and I.
Correct: He sat between you and me.

I now fully understand this rule once I took an English lesson about subject and object pronouns.

The subject is the one that does things. (He sees me)

The object is the one who has the thing done to him. (He sees me)

Another type of object is the prepositional object and it is the one which the preposition is directed at. (He sees it with me)

So, here is a table of subject and object pronouns.

Subject pronouns	Object pronouns
I	Me
You	You
He	Him
She	Her
We	Us
They	Them

So, if you are using a pronoun as a subject, use a subject pronoun. Same thing on the objects.

It’s “between you and me” because “you and me” is the object of the preposition between.

It’s “I know him” because “him” is the object of the verb “know”.

It’s “William and he read” because “William and he” is the subject.