Does the following sentence have any proper adjectives? If so, where?: We will likely follow the Gregorian for the next millennium.
Gregorian (I'm assuming that you're referring to the Gregorian calendar)
Proper adjectives are capitalized, specific adjectives derived from proper nouns.
Examples of proper adjectives:
American (derived from America), Elizabethan (having to do with Queen Elizabeth I's reign), Canadian (derived from Canada)
Gregorian, in this case, is referring to the Gregorian calendar that has to do with Pope Gregory XIII, being his creation.