急需保证书一份英文的!!!!

保证书用不着太长的,下面我给你写了一份.
保证书
尊敬的校领导:
在前一段时间内,由于本人生病了,而没有正常上课,出勤率不够.对此我表示歉意.我保证今后绝不会因其他事而不去上课,我也将好好锻炼身体,提高身体素质.
此致
敬礼
某某
年月
Guarantee
the respect for school leaders:
the former for a period of time, I am sick, but not normal school, attendance not enough. I apologize. I guarantee that the future will not be because of other things rather than go to class, I will also be a good exercise The body, improve physical fitness.
Sincerely
certain date