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用报讯水壶烧过水的小朋友会发现,在水快烧开时,水壶会发出阵阵的啸声。把水壶盖子拿下来仔细观察,你就会发现,这种
Newspaper kettle burned water children will find that when the water is booming, the kettle will send bursts howling. Take a closer look at the kettle lid and you will find that