Could you write a letter to my pen pal, Marco asking him how he's doing? Tell him I have been doing well and that I have been spending all summer fishing. Ask him about his Uncle, Eduardo who had heart surgery recently. Try to keep the letter simple and brief because he is not very good at English yet. Close the letter with "Well wishes, Chris".
Dear Marco, 

How have you been? I am doing well. I have been spending most of my time fishing this Summer. What have you been up to? Also, how is your Uncle Eduardo recovering after his heart surgery? I hope he is doing well. Hope to hear back from you soon.

Well wishes, 
Chris