You can refer to the following structure:

go on vacation

Dear teacher:

Hello!

I can't go to school because I am ill. I need to be treated in the hospital for three days and report to the school after three days, so I need to take three days off, from the date to the date.

I hope the teacher will approve.

I am here to convey

welcome

Requestor: Baidu

What's the date this year?

The last two people who ask for leave should write on the right. Salute should be written on the left of the top line.