The use of numbers in Chinese has national regulations (national standard). Generally, the numbers within 10 are all Chinese characters, such as Monday and Saturday, and the approximate numbers are also Chinese characters, such as seven or eight days, five or six days, and "more than 30 countries" and "elderly people in their sixties" in your article. If the number is greater than 10, Arabic numerals can be used, such as "30 countries". In addition, the numbers before the years of China should be Chinese characters, such as the thirty-six years of Kangxi.

Extended data: