Content in emails that may cause psychological stress to individuals usually has the following characteristics: 1. **Negative feedback**: Direct criticism of someone's work performance or behavior, especially in public or in a team. 2. **Vague message**: Use vague language that makes the recipient feel confused or uneasy, such as "We need to talk, things may not be good." 3. **Sense of urgency**: Applying time pressure, such as requiring a quick reply or completing a task in a short period of time, may make people feel anxious. 4. **Negation or blame**: Convey a negative attitude or make the recipient feel accused, such as "You made the same mistake again." 5. **Personal attack**: Criticism involving personal relationships, or using derogatory language. 6. **Threatening language**: Imply possible consequences, such as job security or other negative effects. 7. **Excessively emotional language**: Use exaggerated or extreme emotional expressions, such as "This is a disaster." 8. **Unclear expectations**: Failure to clearly state the expected results or behaviors makes the recipient feel overwhelmed. 9. **Comparisons with others**: Comparing the recipient to others, implying that their performance is not as good as others, such as "Compared to others, your performance is poor." The above content may deepen the psychological burden of the recipient without attracting obvious attention, causing anxiety or depression. It is important to maintain positive and constructive communication in the workplace and interpersonal communication.