Dear Mrs XX
I beg your pardon, that XX didn`t visited school the last two days. My mum had a heart attack and we all were worried about her, because she is 80 years old. Therefore we spent this days at home in Carinthia. I hope it´s not a problem for xx and that it`s possiblile for her to write the test again. Thanks a lot for your comprehension. Yours sincerely, XX
