Expression that you can not use to greet people is .（ ）
举一反三
- We can use "hello" to greet people in an informal situation.
- It’s unnecessary to use formal expressions and you can say “hi” or “hello” to greet each other in a business meeting.
- You can refer to the ( ) when you greet people.
- In informal situations, you greet people like this
- How can people greet each other informally? ( )_