303. Use the nominative case for a predicated pronoun after is, are, was, were, etc.

Wrong. It was me.

Right. It was I.

Wrong. The best friends I have are her and him.

Right. The best friends I have are she and he.

Revise. It is not whom you think it is.

304. Put a pronoun used as an appositive into the same case as the noun with which it is in apposition.

Wrong. Let’s you and I go.

Right. Let’s you and me go.

Wrong. The principal called in several pupils, Jack and Mary and I.