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

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