when we should put comma
*To avoid confusion, we use commas to separate words and word groups with a series of three or more.
*We use a comma to separate two adjectives when the word and can be inserted between them.
*We a comma when an -ly adjective is used with other adjectives(To test whether an -ly word is an adjective, see if it can be used alone with the noun. If it can, use the comma.)
* We use commas before or surrounding the name or title of a person directly addressed
*We use a comma to separate the day of the month from the year and after the year.
*If any part of the date is omitted, leave out the comma