The Commas Matter poster set introduces six different comma rules. Each poster has two versions of the same sentence–one with a comma and one without. The meanings of those sentences change drastically, most often in a comical way, as illustrated through these funny, retro-themed images. Included are simple explanations for your students as to why a comma is necessary in each sentence.Copyright 2019. Set of six posters. Middle school, high school. 13 x 19 inches each. Cardstock.