1, and 30 years old means 30 years old, which means that a person should be independent in personality, knowledge and career at the age of 30, and now it has become synonymous with a person's 30 years old, commonly known as 30 years old.

2.30 years old from Confucius' The Analects of Confucius: I have five tenths, but I am determined to study. Stand at thirty. Forty is not confused. Fifty knows the destiny. Sixty ears are sweet. Then do what you want, not too much. So when they are 30 years old, men should have achieved something in school.

Men of this age should know what to do and what not to do, and use what they have learned to make their career and family develop well. Such a man is the real success.

Therefore, this word is often used by men in present life, especially men who are about to turn 30. Now we often use this word to refer to a person's self-reliance and the age at which he should get married. Men who have achieved nothing after the age of 30 will be laughed at by others.