I am sorry that I am unable to attend the morning classes because of a bad cold and high fever. Enclosed is a certificate from the doctor who said I must stay in bed today. I will go back to school as soon as I recover.
Im sorry I cant go to school today. I helped the farmers pick apples with my classmates on the farm yesterday. Unluckily, I fell off the ladder and hurt my leg, but I wasnt badly hurt. The doctor asked me to stay in bed and have a good rest. So I ask for leave for two days.
Dear Sir or Madam: Dear Mr Li/Miss Li/Mrs Li,
I beg to apply for two days leave/a weeks leave/7 days leave of absence (请假) from the 7th to 8th of this week. Because I was ill, I want to return/go home to see the doctor.