Answer and Explanation:
To enter a letter is very simple. You should start with a greeting and then write why you are writing this letter. After that you can continue writing the letter normally. Here is an example, where the introduction is in bold.:
Dear friend.
I'm writing this letter to tell you about the surprise birthday party my brothers and I threw for my mom. It was a shame you weren't in town to participate, but I can't guarantee it was a lot of fun.
My brothers and I had already planned this party a few months ago and it was actually easy to organize. We hired a lady to cook the food, made a selection of songs that my mother likes and invited her closest friends. The decoration was up to my younger sister, who wanted to decorate the house like a 70's disco. There was only one problem... How would we get my mother out of the house so she wouldn't see the decoration, the food and the arrival of the guests?
In this regard we need my grandmother's help. As you know my grandmother lives half an hour from my house and we asked her to pretend she was sick and needed my mother to help her with some activities. We asked grandma to hold our mother for about an hour and then ask her to spend the night here at our house and that's what my grandmother did.
Everything went as planned, the party was beautiful and my mother was very happy.
I hope we can have more parties like this and in the years to come, I hope to count on you.
Graciously.
M.S.