Organizing an outline would be your answer.
It would be too obvious for me to write the entire letter for you, but I'll include a list of points that you could include in your own writing style:
* Thanking Lee for his letter, and saying that you are happy that he is having a good time.
* Telling him roughly what you're studying at school (without being boring).
* Write about what you would like to do when you leave school.
* Finally, say that you miss him a lot and look forward to hearing from him soon.
Because if they are both true love or friends they will come to you and you wont have to chase them
That they are soldiers and they believe in God. (1 God at that AND NOT multiple gods)<span />
B, as this is a real theme of a book a instead of examples of what could be happening in the book.