读图，回答

    Hello, I'm Helen. I'm twelve years old. I'm in Garden Primary School. Jane is my classmate. We're good friends. I've got a green bicycle. It's new. I often ride the bicycle to go out and play. Today is Sunday. Jane and I go to visit Aunt Wang by bicycle. She lives in Pudong. She works in a hospital. She likes to make sick people better. She works very hard. It's 5: 45 now. It's dark outside. We must say goodbye to Aunt Wang.

我国使用的人民币硬币，一元币为钢芯镀镍（Ni），伍角币为钢芯镀铜合金，一角币为铝合金或不锈钢。