参考答案

正确答案：
Dear editor，
I'm a middle school teacher and I'm worried about the increasing number of students who smoke in schools．Two years a90，only about l5 percent of the boys smoked．Today 55 percent d0，and even a few girls smoke，t00．
As is well known，smoking does great harm to our health．Facts have shown that many serous diseases，such 8s lung cancer and heart disease．are connected with smokin9．When one smokes in public places，harm is done not only to himself but also to all the people around．And if one smokes，he wi11 have to spend a lot of money on it．
So I wish to give the students a piece of advice：give up smoking and keep yourselves healthy．
Yours truly，
Zhao Ming
【写作提示】众所周知，吸烟有害健康。实践证明，许多疾病都和吸烟有关。在公共场所吸烟，不仅对自己身体有害，还危害他人。此外，经常吸烟，还会花掉大量的钱。