Dear Peter, I would like to know if I could ____ (要求) a casual leave of absence for one day on ____ (2月8日), this Wednesday. This morning I received a telephone call from my ____ (牙医), urging me to go to him for immediate treatment of my teeth. I have been experiencing a serious pain, depriving me of my sleep during ____(上一). The situation could worsen,should ____ (注射)occur. Concerning my classes I will miss, I think I can ____ (弥补)them in the evening at home. If possible, could you please send me the learning materials used ____(课堂上) ? I apologize for the ____ (不便)my absence from study may cause. Thank you for your consideration and I'm ____ (感激的) for the care and help you are generously offering ____ (一直)! Yours, Ann