谁可以给我一个英语作文？

我的要求是写一个：别人请求我去参加他的派对，可是我没有空，不能去！

字数要60个词，也就是一个拒绝信，但是要求委婉一点！

另外把中文写上，谢谢

Dear XXX

Thank you very much for inviting me to your party. I'd love to go,but I can't.I am really busy on Saturday. On Saturday morning ,I have to stay at home and look after my grandpa ,because my gandpa is ill in bed ,and my parents are going out .In the afternoon,I am having a piano lesson .After that ,I have to help my mom do the housework.In the evening,I have to study for the English test .I hope you are having a good time . Happy Birthday!

XXXXX

谢谢你的邀请，我很喜欢，但是我不能去，我在星期六真的很忙。在星期六早上，我要呆在家里照顾我的爷爷，因为我爷爷生病了和我父母不在家。在下午，我要帮助我的妈妈做家务。在晚上，我要为英语考试而学习。我希望你玩的快乐。生日快乐！