Comma between adjectives

Rule 4 Use a comma between two or more adjectives that come before a noun only if you can reverse the order of the adjectives. 

In the first example, the commas are used to separate similar words (adjectives) which are used to describe another word (a noun). When we write a list of adjectives in front of a noun we use commas to separate the adjectives. It is not usual to put a comma between the final adjective and the word that it is describing. 

Use commas to separate adjectives of equal emphasis that modify the same noun. To determine if a comma should be used, see if you can insert the word and between the adjectives if the phrase still makes proper sense with the substituted and, use a comma. 

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