I really want to say thanks to you because you not only teach ue a lot of knowledge, but also are concerned about us. I still remember that you worried about our health last spring, when influenza A spreaded rapidly around the city. You, my dear teacher, asked us to wash hand and take a bath frequently. You also suggested us to open the windows and not go to the place having many people. You recommended us to drink more water and form a good habit. You came early and back late to spray drug. It was very painstaking.My dear teacher, thanks again.