No commas in between different types of adjectives

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi teacher Yankee,

You wrote:

No commas in between different types of adjectives in a series. (1)

Could you tell me the difference in (1) and (2)?

No commas between different types of adjectives in a series (2)

Q

2

.
The word in is optional. It doesn’t change the meaning here.