Both of Greg's original examples are correct. The use of comma between the last two words is optional to the best of my knowledge.
The first rule of English when you start getting advanced is that most rules are meant to be broken. Ernest Hemingway wrote in short choppy sentences. e e cummings did not capitalize. To cite another example, typing a sentence in all caps is typically considered bad form, but if you're writing a long fictitious piece and are trying to describe a giant or dragon talking, making their sentences in all caps may convey to the reader the intensity and volume of the voice in question. A long run on sentence is also typically considered bad form, but if you're describing a hyperactive person ranting for three minutes, it may be a good decision, because it more accurately describes what is happening than splitting the speech. Judgment is more important than thinking by the box. Comma use is no different. There are times when by convention you should use a comma, but it's more effective not to. Among other things, I do it in stream-of-consciousness situations where my character's speech is an outburst rather than planned.
The first rule of English when you start getting advanced is that most rules are meant to be broken. Ernest Hemingway wrote in short choppy sentences. e e cummings did not capitalize. To cite another example, typing a sentence in all caps is typically considered bad form, but if you're writing a long fictitious piece and are trying to describe a giant or dragon talking, making their sentences in all caps may convey to the reader the intensity and volume of the voice in question. A long run on sentence is also typically considered bad form, but if you're describing a hyperactive person ranting for three minutes, it may be a good decision, because it more accurately describes what is happening than splitting the speech. Judgment is more important than thinking by the box. Comma use is no different. There are times when by convention you should use a comma, but it's more effective not to. Among other things, I do it in stream-of-consciousness situations where my character's speech is an outburst rather than planned.