I am sorry that I haven't written in ages, but I have been really busy. You know we moved to a flat in London last year? Well, we have worked on our flat since then. You must come visit us the next time you're in London. Meanwhile, I have started to run again. You know how I used to run when we were in school? Well, last year I decided that I needed to get fitter, and I joined sports club. And guess what? I just ran the London Marathon! I finished it in five hours fifteen minutes. I felt very proud of myself! And I could be five kilos lighter! When will you come to London (or: When are you coming to London)? It will be great to see you again. Write soon!

I was (am) sorry that I didn’t write for ages but I have been really busy. You know we moved flat to (to a flat in) London last year? You must be to visit us when you next come in London. (You must come to visit us the next time you're in London) Well, last year I decided that I needed to get a fitter (get fit) and I joined (a) sports club. I just ran in (the) London Marathon! I was very proud of myself! ("I felt that " is unnecessary) When (will) you come (to) London? Write soon. (this isn't a good closing)