Write a leave letter to your teacher.
To,
The Teacher

Sir/Madam,
           This is to inform you that I will be going out of station for 3 days from <date> to <date>, to attend my sister's wedding celebrations.
           I request you to kindly consider this and  grant me leave.

Yours faithfully,
XYZ
<START_INST>Write a leave letter to your teacher.<END_INST><START_CTX><END_CTX><START_A>To,
The Teacher

Sir/Madam,
           This is to inform you that I will be going out of station for 3 days from <date> to <date>, to attend my sister's wedding celebrations.
           I request you to kindly consider this and  grant me leave.

Yours faithfully,
XYZ<END_A>