I am sorry that I won't be able to..…
I am sorry to tell you that I can't..…
I am writing to ask you for a day's sick leave.
I have to ask for two days'leave.
Dear Mrs. Lawson，
I am sorry that I can't come to school today。I have caught a bad cold and I feel terrible。Yesterday__________________。 Then I__________________and went home____________________。 After dinner，I felt_______________________ 。The doctor___________________________。I hope you can give me a leave。
Dear Mrs. Lawson，
I am sorry that I can't come to school today。I have caught a bad cold and I feel terrible。Yesterday I had a football match with my classmates and was wet all over。 Then I took off my sweater and went home with only a T-shirt。 After dinner，I felt terrible and got a fever。I had a headache and a sore throat 。 The doctor gave me some pills and asked me to have a good rest。 I hope you can give me a leave。
Dear Mr/Ms XXX;
Today I'm writing to you to ask for a five-day leave， for I've got cold last night with carlessness.
This morning my mother took me to see the doctor，who told me to stay in bed for some days. So I am very sorry to be absent from school， especially your interesting lessons. I'll be sure to make up for the missed lessons after I recover from the illness.
Dear Ms Ma，
I apologize that I cannot go to school today. Last night my mother had a high fever and coughed badly. I think that she has got flu. She didn't have a good sleep and is very weak today， so I will go to Tiantan Hospital with my mother， and then stay at home to attend her. Because of this I have to ask for leave. I will appreciate you very much if you can allow my leave.
March 6th， 2013
Dear Mr Li，
I’m sorry to tell you that I have to ask for sick leave for the whole afternoon class. Because I have a heavy headache now and feel very sick. I think I have to ask for sick leave to go to hospital for medicine. I will attend the next day classes on time.
1.i'm writing to you to ask a sick leave.我在给你写信请病假。
2.i ask you for sick leave of three days.我请3天病假。
3.i'm sorry that i can't go to school today，so i want to ask for two days of sick leave.很抱歉今天我无法上学了，所以我想请两天病假。
4.i wonder if you could give me your permission.你是否同意我请假呢。
5.i hope you can approve my leave.望准假！
6.your kind permission will be greatly appreciated.承蒙惠准，感激不尽。
7.i'11 go back to school as soon as i am well enough.and i'1l do my best to make up for the missing lessons during my absence我病一好了就会尽快回校。并且我会尽我所能去补上所缺的课程。
8.sick leave 病假a casual/absence leave 事假
9.i am very/really/terribly/extremely sorry to te1l you that i cannot attend your english classes today.很抱歉我今天不能上您的英语课。
10.i have to go to see the doctor.我得看医生。
11.i want to ask for four days'leave from tuesday to friday.我想请假4天，时间是从周二到周五。
12.i enclose a doctor's certificate.我附上了医生证明。（注意：有的请假条为了说明其请假事由是真实的，在正文之后另起一行，写上这句）