500
Dear Nico,
I was just informing you that you have very bad grades. Nico, you have to bring those grades up. You are a very smart, young man, but your grades don't reflect that. I mean, yes you do have a 97 in language arts, but all your other classes are very low grades. Just listen to your teacher.
yours truly, Mr. Smith
Comma rule 2: use a comma to set off names in a direct address.
Comma rule 11: use a comma to separate the clauses in a compound sentence
Comma rule 4: use a comma after introductory words when it begins a sentence