Jenny 邀请Jane在星期一参加生日晚会。但是Jane 那天晚上要参加数学考试，没时间去。请帮Jane写一封信表示感谢，她同时送上一份礼物，以示祝贺。时间是5月20日。
May20th,
Dear Jenny,
I'm glad to hear your good news. Thank you for inviting me to your birthday party. But I'm afraid I can't come. Because I'll have a math exam on Monday evening. Here is a gift for you. I hope you will love it.
Happy birthday!
Sincerely yours,
Jane