What's the difference between modesty and respect?

1. Different usage: Caution is mainly used at the end of letters to show respect and courtesy to the recipients. Sincerity is mainly used in more formal occasions to express respect and respect for each other.

2. Different tone: Cautious tone is respectful and serious, with a certain sense of solemnity. The tone of respect is more respectful and humble, expressing extreme respect and respect for each other.