根据下面短文内容，在短文的空格处填上一个恰当的词，使短文完整、通顺。

Today is January 5th. It's a fine day. It's Betty's . After school, she gets home sees a new red box on her bed. She opens it.

There is nothing but a piece of paper the box! Betty takes it out and reads, "Dear Betty. I'm your present (礼物). You find me in the living room." Betty says, " is my present? Is it a book? A watch?" Then she runs to the living room. She finds her parents there and look at her happily. At , she sees her present. It's orange bike. "Happy birthday, Betty!" Her parents both say. Betty is very and says, "Thank you very much. I it!"