Hi Sasha, Your sentence: "I'm sorry, but there are _________ tickets left." Here, you need a determiner to provide some information about a quantity, and "no" can be used as a determiner for that purpose. "None" is not an appropriate answer here, because it is not used immediately before a noun. Examples (incorrect): There is none tickets. There is none response. However, "none" can be used with "of + determiner + noun". So, if you really wish to use "none", the sentence can be modified as: "None of the tickets was left." I hope this helps you.

Good; There are no tickets There are none Bad: There are none tickets There are no

None is a pronoun that you can use instead of the word TICKETS. There are NONE left. There are no TICKETS left.

After "none" you don't use anything because the "one" part replaces the noun in question. If you don't have any previous context then you can say "none of the tickets", then it would work but not more than that.

no tickets left <= only на всякий случай напоминаю: в лексике нет "почему" все "почему так" они про грамматику