脖子扭伤 how to write a note to my P.E teacher

To Mr/Ms 老师名字:
I had sprained my ankle yesterday when I was playing basketball.
一下就是说你不能上P.E.了.
I will be unable to participate in any physical activities in class.Please grant me the permission to sit out on today's class or following classes if necessary.Thank you.

Dear teacher:
My neck was badly sprained when I played basketball yesterday.The doctor said I should have a good rest,so I couldn't take part in any physical exercises. Enclosed with my case history.
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