Confused: none/all

[Number7]

Dear all,

I have one quick question. I read two contradictory statements concerning "all" and "none".

One book says: "None of the shirts are cool." is correct since plural/singular depends on the "of..."-part (the same with some, any, ALL, most).

Another book says: "None of the shirts IS cool" is correct since "none" is always singular.

The same question applies to "all": One book says: "all" always requires ARE, the other book says: it depends on "of"-part

Which of the books is correct? Is "none" similar to "each" and "every" (ALWAYS singular) or does it depend on the "of"-part? What about "all"?

Thank you very much in advance!

[reachac]

Some, All , none, any , most are 5 indefinite pronouns that can beeider singular or plural depending upon the contextual usage