Imagine you have a friend from Japan and he/she sends you a letter telling you he/she is going to travel to Monterrey. Write him/her a letter with recommendations of places to visit and activities to do.
Imagine you went on a trip with you friends to Disneyland. Write a letter to your grandmother about what have you been doing
A friend of yours missed class today and you need to send him/her a letter about what happened at school today.