Should there be a comma before but or after?

The placement of a comma before or after "but" depends on the grammatical structure of your sentence. Here's a breakdown:

Comma Before "But"

* When "but" introduces a contrasting or opposing idea in a compound sentence:

* *The weather was beautiful, but the beach was crowded.*

* *I wanted to stay, but I had to leave.*

Comma After "But"

* Generally, you don't use a comma after "but."

Exceptions:

* When "but" is used as an interjection:

* *I'm going to the store, but, wait, I need to grab my wallet first.*

* When "but" introduces a parenthetical phrase or element:

* *The movie was excellent, but, as usual, I fell asleep halfway through.*

Key Takeaway:

Think of "but" as a connector between two independent clauses. If the clauses could stand alone as separate sentences, a comma usually goes before "but."