Write a letter to your class teacher asking for 2 days of leave.
To,
The Class Teacher,
Bright School,
Bangalore.
Subject: Application for leave
Respected Madam,
I am student of your class X. My roll no is [xxxx]. I am suffering from a high fever and cold and the doctor has advised me to take bed rest for 2 days. So, I will not be able to attend school for 2 days from DD/MM/YYYY to DD/MM/YYYY. Hence, kindly request you to grant me leave for 2 days.
Yours Obedient Student
ABC
Class X
Roll No. [xxxx]
DD/MM/YYYY