to a human, a time period of 10 years or more years is considered very long
great_year is time_period. decade is not 10_years. long_time is time_period. most_years is 365_days_long. forever is not long_time. years has 366_days decade is 10_years. no_human has lived_longer_than_150_years decade is time_period. forever is long_time.