Object of a Preposition: All of Us, Together Now

Matthew writes:

Hey Snarky! Yesterday my teacher said 'All of us teachers are working together on a plan.' Is that correct or awkward grammar? Shouldn't he have said 'All of we teachers'?

Your teacher is positively diabolical. Not only is his sentence structure flawless, but he gave me a reason bring up one of the most dastardly of all grammar chestnuts: the object of a preposition.

Your teacher's sentence is tricky for a few reasons. For starters, the subject is not a single word but a phrase, 'All of us teachers,' which happens to include the word us. We are accustomed to seeing us as a personal pronoun functioning as the object of a sentence, but here it is the object of a preposition, which is part of the subject of the sentence. Confused?

Here's the rule: A noun or pronoun that follows a preposition and completes its meaning is the object of the preposition.

Let's look at 'All of us teachers'. Since the phrase includes a preposition, 'of', the noun that follows it turns into an object—but only of that phrase, not of the entire sentence. In this case, the object of the preposition is 'us teachers'.

Your teacher could have said We teachers are working together on a plan. Then we could have avoided this lesson altogether.

Quick rules:

• The noun or pronoun following a preposition is the object of that preposition.
• A prepositional phrase can be the subject of a sentence or the object of a sentence.
• The subject of a sentence doesn't have to be a single word; in fact, it's often a phrase.
• The object of a preposition is not necessarily the object of the sentence.

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