情景：班里來了一名新同學(xué)，學(xué)習(xí)跟不上。作為班長你要主動(dòng)幫他補(bǔ)課，放學(xué)時(shí)，你請同學(xué)給父母帶一張便條。
任務(wù)：請你用英語給父母寫一封50左右的便條。告訴他們：

1 為什么今天回家會(huì)晚一些； 2 大約補(bǔ)多長時(shí)間的課； 3 什么時(shí)候到家。????

請用下面格式：
Dear mum and dad ,
? ……
??????????????????????????????????????????????????? Bingbing

范文：

Dear mum and dad ,
I’m afraid I have to go home late today , because we have a new classmate . He is very poor in maths and English , so I need to help him to catch up with the class after school . We will stay at school for about an hour . I will get home at about six .
???????????????????????????????????????????????????? Bingbing

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