posted by Samatha Priest .
With five gallons of gas.
This is not a complete sentence.
Once you write a complete sentence, please repost and we'll help you with punctuation, if necessary.
With five gallons of gas the car will run.
Now it's a complete sentence -- and you need a comma after "gas" -- OK?
With five gallons of gas the car will go far.
See #3 for this particular comma use.