Invitation and Letter / Email

Invitation
Invitation is the message or note lesed in inviting. 
     The function of infitation is to ask some on to go to a place or to do something. Weusually use the " invitation " in our daily life , for exsampel if we want to hold and event like abirthday party. Weuse the invitation and if we want some in to do something, like if we want our friend to halpus. We use