The fact that punctuation marks are not used correctly and in place is the biggest factor that disrupts the integrity of meaning. For this reason, it is necessary to follow the rules of punctuation in order to express the desired message correctly. Period: The period is used at the end of sentences and in abbreviations. ∗ I love reading storybooks. ∗ Mr. Clark Comma: The comma is used between sentences and words that follow each other. ∗ I can speak English, French, Germany. ⇒ A comma is not commonly used before “and” at the end of a one-word list. ∗