How to write a letter to the teacher when the child has a fever and asks for leave?

Children who have a fever and ask for leave can write to the teacher like this for reference only:

1, Dear Teacher xx: My son needs treatment for a fever and needs to ask for leave. From _ _ to _ _. I hope your approval! Hereby, pay tribute! Applicant: XXX, XX, XX.

2. Dear xx teacher: XX children in XX class need to go to the hospital because of fever and illness. I hereby ask the teacher for leave for XX days (that is, from XX to XX). We hope that the teacher will approve them after they recover. Leave: XXX, parents of children, XX, XX, XX, XX.

3. Dear Teacher XX: Hello! Child XX, who is sick with a fever, needs to take XX days off. (Date of Leave: Month Day-Month Day) Please ask the teacher for approval. Salute! Applicant: xx year x month x day.