Dear Yangyang,
I am sorry to hear that you have a cold.You said that you had a headache.In my opinion,you should go to see a doctor.If the doctor gives you some medicine,you should follow the doctor's advice and take the medicine on time.Besides,you should drink lots of hot water and have a good rest.If you get better,you can write to me because I am really worried about you.Hope you can get well soon.
Yours,###
亲爱的洋洋,
听到你感冒了,我很难过.你说你头疼,那我觉得你应该去看医生.如果医生给你开了药,你一定要听医生的建议,按时服药.此外,你要多喝热水,好好休息.如果你感觉好多了,就给我写信告诉我,因为我真的很担心你.希望你能很快康复.
你的,###