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I.After It Is Dark Son:Mum,is it true that theearth goes around the sun? Mum:Yes,it is. Son:How then when there isno sun in the sky at night? 天黑之后儿子:妈妈,地球绕着太阳转是对的吗? 妈妈:当然是对的。儿子:那么晚上没有太阳的时候呢?